An Analysis of Coherence and Cohesion in English Majors’ Academic Essays

This research investigates coherence (how ideas are logically connected) and cohesion (how sentences flow together) errors in essays written by junior English majors. Analyzing 80 essays and conducting 10 interviews, the researchers identified common errors and usage patterns. Using Halliday and Hasan’s (1976) framework for cohesion and Oshima and Hogue's (2006) framework for coherence, the findings reveal frequent use of lexical cohesion, such as repetition and synonyms, but also misuse of cohesive devices. The study suggests that clear instructional interventions should be developed to improve writing skills, and regular feedback should be provided. Teachers should demonstrate the use of cohesive devices to connect ideas and enhance coherence and peer review activities can also help students learn from each other's writing. Future research should consider longitudinal studies and cross-institutional comparisons to track progress and identify common issues.


Introduction
Writing skills are essential in many aspects of modern society and crucial in various situations and jobs.They help people share their thoughts and ideas, organize and summarize information, and convince others (Ahmed, 2019).Additionally, writing stimulates thinking, assisting people in developing the ability to synthesize, analyze, and reflect (Rao, 2007).

Literature review
Importance of Coherence and Cohesion Halliday and Hassan (1976) introduced the concept of cohesion in their work "Cohesion in English," defining it as the various methods available for connecting a part of a text with what has previously been mentioned.Also, some experts define cohesion as phrases linked together in ways that the discourse itself can manifest clearly and presentably to readers (Bailey, 2003;Renkema, 2004).Upon using cohesion, the user is "tying" or "gluing" their words to set up a clear and logical meaning for the reader, thus giving the text its "flow" (Moxley, 2015).
Cohesion performs its function through what are called cohesive devices.Hedge (2005) describes cohesive devices as tools that connect parts of a text into logically related sequences, indicating the relationships between ideas to clarify the writer's intentions.Cohesive devices consist of two major categories, including grammatical cohesion and lexical cohesion.Halliday and Hassan (1976), in their widely accepted taxonomy of cohesive devices, identify five subcategories: reference, substitution, ellipsis, conjunction, and lexical cohesion.
Coherence, like cohesion, is also essential in writing.It means arranging ideas logically in a text so readers can easily understand and find meaning.If each sentence is good, without context from previous sentences, readers may be confused (Halliday & Hasan, 1989), or a sentence can confuse readers if it starts unexpectedly.Furthermore, Kuo (1995) explores how coherence can be achieved through contextual ties, like using shared knowledge between writer and reader.
Research into coherence and cohesion has sparked debates among experts.Some researchers put the two terms as "two faces of the same coin", interwoven and vital in constructing a text's meaning (Farida & Arifin, 2020;Bui et al., 2021;Lismay, 2020).Others try to differentiate the two concepts and insist that cohesion and coherence do not always go together (Oller & Jonz, 1994;Widdowson, 2007).
As Tanskanen (2006) puts it, "successful communication depends on both cohesion and coherence, which are simultaneously independent and intertwined."In conclusion, based on this explanation, coherence and cohesion can indeed stand separately and still perform their designated functions, but it would be most favorable for writing to have both devices.

Error Analysis
Error analysis plays a crucial role in second language acquisition as it helps learners identify their mistakes, allowing them to make the necessary adjustments to correct and improve upon those errors.Hasyim (2002) concludes that error analysis is a tool used to name, categorize, and clarify learner's errors during their performance in writing and/or speaking skills.He also states that analyzing activities can help teachers obtain information regarding common errors made by learners.Meanwhile, Ulla (2014) believes error analysis involves observing, analyzing, and categorizing deviations from second language rules to uncover the underlying systems guiding the learner's language use.For example, Do and Le (2023) found common collocation errors regarding verb + noun and adjective + noun, which contribute to learners' lack of competence in their essay writing.
Error analysis is defined as a technique to point out, group, and assess the inappropriate language usage conducted by learners using a set of rules provided by linguistics (Ingemann & Crystal, 2008).Simply put, error analysis is a technique that teachers use, following a set of principles, to reveal students' mistakes in writing or speaking activities.Ho's (2024) study revealed that the most common issues were with referencing, citation, coherence, cohesion, plagiarism, and paraphrasing.Problems related to lexicon and grammar were less frequent and were the group of issues that EFL students encountered less often in academic writing.
It also helps teachers identify, classify, and interpret such mistakes accurately and gives them a greater view of student errors.For the sake of this study, the analysis focuses on analyzing students' mistakes in coherence and cohesion.
Cohesion Framework Halliday and Hasan (1976) identified five properties through which cohesion can be established, as detailed in Figure 1 employed by Rahman (2013).
Firstly, reference is arguably the most frequently used cohesive device in any writing.It involves using a word to refer to a preceding or subsequent item.This concept can be divided into two sub-types, i.e., endophora and exophora.Endophora is further classified into anaphora (referring to a preceding item) and cataphora (referring to a subsequent item).The key distinction is that endophora refers to an item within the text, whereas exophora refers to an item outside the text or a surrounding object, requiring the listener or reader to understand the context to grasp the meaning.For example, a person might point to an object and say "this" or "it," as in "I like this." Cohesive reference can be categorized into three main types: personal, demonstrative, and comparative.Personal reference refers to the use of personal and possessive pronouns such as I, you, we, they, he, she, it or his, her, them, their, etc. to create text cohesion.For example, in the sentence "Ariston, the Greek slave, is painting.He stands at a wall with his brush in hand.", the personal pronoun he refers to Ariston since they are one and the same.The pronoun also refers to "the Greek slave," which is an appositive noun phrase that gives the reader more information about Ariston.The possessive pronoun in this setting refers to the relationship between Ariston and the brush.Demonstrative reference achieves its cohesion through determiners (the, this, that, these, those) and adverbs (here, then, now, then) because they refer to someone or something in a text or the environment.Comparative reference is used when users need to contrast or compare at least two elements, and this type of reference consists of adjectives and adverbs.Adjectives of identity (same or equal), adverbials (likewise, otherwise, etc.), and other comparative adjectives (better, worse, faster, greater, etc.) are all evidence of comparative reference.
Secondly, substitution involves replacing one element with another to avoid repetition and occurs in three forms: nominal, verbal, and clausal.Nominal substitution replaces a noun or head noun with "one" or "ones."Verbal substitution functions, similarly, using the word "do" (in its various forms) to replace a lexical verb or an entire verb phrase.Clausal substitution employs the words "so" and/or "not" to substitute for a presumed clause in positive or negative contexts.
Third, like substitution, ellipses have three main types: nominal, verbal, and clausal.The difference between ellipses and substitution is that ellipses leave out parts of the text instead of replacing them.Because of this, ellipses are not usually used in academic writing and are more common in everyday speech.For example, nominal ellipsis omits a noun or noun phrase, such as in "I want a piece of cake, and she does too," where "does" replaces "wants a piece of cake."In verbal ellipsis, part of the verb phrase is left out, like in "She can play the drums, and he can too," where "can play the drums" is omitted after "he."Clausal ellipsis removes an entire clause, such as "She enjoys singing, and he, jogging," where "enjoys jogging" is not repeated.These types of ellipses help make speech more concise by avoiding repetition, which is useful in everyday conversation.
Fourth, conjunctions are semantic relations that connect sentences through adverbs or connectives.There are four main types of conjunctions: additive, adversative, causal, and temporal.Additive conjuncts allow writers to add extra information.For example: "Plastic poses a danger to animals.Furthermore, it destroys natural habitats and could potentially harm humans."Adversative conjuncts illustrate the contrast between sentences, such as in: "Hades is portrayed as an evil, ruthless god.However, he is known to be fair and loving to his wife."Causal conjuncts show the cause-effect relationship between sentences: "He stayed up late last night.As a result, he missed the bus this morning and was late for work."Temporal conjuncts are used to show sequences of events and create a chain of actions.For example: "I watched TV yesterday.Then I remembered I had a paper due in a few days.Afterward, I wrote the paper in a panic."Finally, lexical cohesion involves repeating words from a previous sentence or using synonyms or words within the same classification or category.This cohesive device includes four main types: synonymy, repetition, hyponymy, and metonymy.

Coherence Framework
Coherence refers to the extent to which readers can understand a given context through proper idea placements.Illogical or incoherent writing can cause confusion.Oshima and Hogue (2006) describe coherence in writing as the seamless flow of sentences, where each sentence logically connects to the next without abrupt transitions.The two authors suggested four ways to achieve coherence.
A simple way to achieve coherence is to repeat key nouns.Doing this will help emphasize the main theme or character and help build focus in one's writing (Maria, 2015).However, Ahmed (2019) warned that this method should be used in moderation since too much repetition would cause readers to get bored and eventually lose focus.
Another way of achieving coherence is by using consistent pronouns.An essay would be incredibly boring and repetitive to read through if it mainly consists of repetition.An easy remedy is to use pronouns in place of the repeated nouns.This will not only reduce reiteration but also improve diversity in the discourse (Maria, 2015).An important note for this segment is consistency.To build coherence, a writer must ensure that the pronouns address the same person and/or thing (Ahmed, 2019).Moreover, Maria (2015) warns that writers should avoid using the indefinite "you" as it causes vagueness, and the tone would be overly casual.
Transition signalsoften called linking words or adverbials -refer to using specific words or phrases, such as however, because, etc., to create links and transition between ideas.As Ahmed (2019) stated, "these devices indicate to the reader the specific relationship between what was said and what will be said.They can be added to a text to make it clear how the sentences are related to each other".
Arranging ideas in logical order is of paramount importance in achieving coherence.If texts are not arranged in any logical order, the writing will most certainly be incomprehensible.Regarding this element, there are several kinds of logical order, namely chronology, importance, and contrast (Ahmed, 2019), which means (1) chronology pertains to time, meaning that the events or contents in an essay are arranged in sequential order, (2) importance refers to discussing ideas in either increasing or decreasing order of significance and (3) contrast functions by arranging ideas so that they are compared.

Previous Studies
Many studies have examined how cohesive devices are used in different languages and contexts, providing important insights into how students use these tools in their writing.Yang and Sun (2012) studied cohesive devices in argumentative writing with 60 students.Their mixed-methods study found a strong link between the correct use of cohesive devices and writing quality, although many students misused specific cohesive items.Kafes (2012) focused on lexical cohesion in essays written by intermediate-level students in Turkish and English, finding strong similarities in their use of lexical cohesion but a common issue with vocabulary repetition.Rahman (2013) examined cohesive devices in descriptive writing by Omani student-teachers.This qualitative study found significant differences in the use of cohesive devices between firstyear, third-year, and native speakers, with repetition and reference being common areas of overuse and errors.Has (2021) analyzed cohesive and coherence devices in student writing among 100 students, showing that all cohesive devices were used, but the substitution was notably missing, causing issues in producing cohesive and coherent texts.Bui et al. (2022) studied Vietnamese college students' writing, involving 168 senior-year students.This mixed-methods research found that references, conjunctions, and lexical items were the most frequently used cohesive devices, though misconceptions often led to errors.Oanh and Huynh (2023) focused on cohesive devices in argumentative writing by EFL learners, specifically junior English majors at Thu Dau Mot University, Vietnam.Their qualitative study found that references, conjunction, reiteration, and collocation errors were common, often due to grammatical issues related to their mother tongue.
These studies show the importance of cohesive writing devices and the challenges students face in mastering their use.The present study aims to build on this work by investigating how cohesive devices are used and how coherence is achieved in student writing at a private university.It seeks to better understand effective writing practices and support teachers in guiding students to develop cohesive and coherent texts.

Research Questions
This study aims to investigate student's competency in essays in terms of coherence and cohesion.The research goes over the essays from students of a faculty of foreign languages, counting and documenting cohesion-and-coherence-related errors and figuring out how competent the students are.This study intends to explore student's competency in (1) using cohesive devices and (2) creating coherent writings.
Therefore, it aims to answer the following questions: 1) How frequently do English majors use each type of cohesive device in essays?
2) What types of cohesion errors do they make in essays?
3) How frequently do English majors use various criteria to achieve coherence?4) What are the reasons for their errors?

Pedagogical Setting & Participants
The study was carried out at a private university in Ho Chi Minh City, Vietnam.The institution provides comprehensive language education programs, including majors in English and Chinese languages.Regarding the English language program, the faculty offers a four-year English language program designed to equip students with advanced language skills.This program prepares students for careers that require high English proficiency, such as translation, interpretation, teaching, and working in various business sectors.Through rigorous training in reading, writing, speaking, and listening, students develop the competency needed to excel in professional environments that demand strong English language abilities.
The study employed convenience sampling, selecting 80 volunteer participants from the population of English major students who were all in their junior year and aged 20-21.The sample consisted of 32 males and 48 females, with intermediate English proficiency ranging from higher B1 to B2 levels.They had learnt three courses of academic writing before starting with how to write an essay, meaning that they are in the training program's second year or fourth semester.

Design of the Study
The current research used both quantitative and qualitative approaches.By using Halliday and Hasan's (1976) taxonomy for cohesion and Oshima and Hogue's (2006) taxonomy for coherence, the study aimed to analyze competence in writing cohesive and coherent essays.Specifically, the study analyzed manually the frequency with which students use each type of cohesive device and various devices for coherence.The study also investigated the errors students commit when applying cohesion and coherence.From there, cohesive devices and coherent devices were collected and analyzed.Then, errors of each respective mechanic (cohesion and coherence, respectively) were identified and classified into types based on the taxonomies.Finally, semi-structured interviews were conducted to determine the student's opinions on cohesion, coherence concepts, and errors.

Data collection & analysis
The study used written essays and interviews as its main data collection instruments.As for essays, participants were given a writing topic and 40 minutes to complete an essay in class under the observation of the researchers.The following topic was chosen because of its up-todate problem that is believed to be the most concern after graduation, i.e., "Nowadays many people choose to be self-employed, rather than to work for a company or organization.Why might this be the case?What could be the disadvantages of being self-employed" (Cambridge IELTS 14, 2019).
Overall, the researchers collected 80 essays for documentation and analysis, comprising approximately 24,000 words.The primary objective was to identify cohesion and coherence errors in students' writing.Initially, the researchers read through the data set to identify cohesive and coherent devices used in the essays, and then the errors were classified into types and subtypes based on existing taxonomies.Next, errors were documented according to their types (Table 2), which were categorized into four main groups: misuse, redundancy, omission, and overabundance (Ong, 2011;Rahman, 2013).Additionally, the frequency of each type of cohesive and coherent device and the frequency of errors was recorded to provide a comprehensive view of the students' use of these devices and the common challenges they faced.Regarding the 20-25-minute interviews, the researchers interviewed 10 volunteers (coded from S001 to S010) using semi-structured questions.This approach allowed for flexibility while staying focused on key topics.The researchers used Vietnamese to assist the participants to better understand the topic and for convenience.Doing this helped individuals get their ideas across more easily and made the interview process happen smoothly.The purpose was to assess their understanding of cohesion and coherence concepts in their essays.The questions aimed to uncover the reasons behind any mistakes and to gather insights into their thought processes while writing.The researchers employed thematic analysis to analyze the interviews.This method involved transcribing the interviews, coding the data to identify recurring themes, and organizing these themes into broader categories that reflect the participants' perspectives and experiences.

Findings
Research question 1: How frequently do English majors use each type of cohesive device in essays?As seen from Table 3, the students employed lexical cohesion most frequently, accounting for 40.38%.This was followed by reference and conjunction, which accounted for 32.43% and 25.8%, respectively.The two remaining devices, substitution, and ellipsis, were used sparingly, with ellipses appearing 44 times (a mere 0.8%) and substitution occurring 31 times, contributing only 0.5% to the total.As mentioned, cohesion and its error share a similar pattern, in which the more cohesive devices were used, the more errors were made.The students applied lexical cohesion the most, which also resulted in the highest number of errors with this device.From Table 4, out of 163 errors, 73 (approximately 45%) were due to overabundance, 49 (30.06%) to misuse, 39 (23.92%) to redundancy, and 2 (1.22%) to omission.Although reference was used more frequently than conjunction, students made fewer errors with reference.From Tables 3 and 4, there were 1,775 instances of reference with only 89 errors, while conjunction had 1,412 instances with 144 errors.

Research question 2: What types of cohesion errors do they make in essays?
Most conjunction blunders fell into the misuse and omission error types, with both consisting of 55 errors (38.19%).Redundancy is next with 27 mistakes (18.75%), and overabundance is with 7 errors (4.86%).For reference, its 89 fumbles mainly revolved around misuse and redundancy, 56.17% and 30.33%, respectively.At the same time, omission and overabundance shared few errors, only about 7.86% and 5.61%.In summary, students made most of their errors through misuse and redundancy of three cohesive devices.However, many omission mistakes were also witnessed in the conjunction device, and the same goes for lexical cohesion and the overabundance type.

RQ3: How frequently do English majors use various criteria to achieve coherence?
From Table 5, the data revealed the various devices or methods students employed to achieve coherence in their essays.Using the coherence framework proposed by Oshima and Hogue (2006), the author identified 5,907 unique coherence devices in 80 essays.Of these, 1,961 were instances of repeating words or synonyms, making it the most commonly used method to achieve coherence.Next in line was using correct pronouns, with 1,495 instances comprising just over a quarter of the total device count.Following closely behind are transitional links with their 1,412 appearances, contributing 23.90% to the coherence count.Lastly, it is a logical order with 1,039 (17.58%) unique sentences that helped build and maintain coherence throughout the students' essays.After the errors for both cohesion and coherence had been identified, there was a need for insights into why the students could make these mistakes.Careful inspection revealed that students overused lexical cohesion, namely repetition and synonymy.They also misused or omitted plenty of connectives, leading to large errors in both cohesion and coherence.As for the reference device, students primarily used it incorrectly or unnecessarily.Regarding coherence, a logical order was the criterion with most blunders.Therefore, these were the focus of the interview, as shown in the results.

Unfamiliarity with the concepts
To establish a foundation and introduce the topic to all participants, the researchers inquired about their familiarity with the concepts of cohesion and coherence.Six out of ten students partly understood those terms, while S006 expressed confusion, believing two terms were synonymous.

Limited vocabulary and overabundance
Afterward, each student was asked why these cohesion errors could occur in essays.Most attributed limited vocabulary to misuse and overabundance errors.They continued to explain that since students' word pool was narrow, they could only go so far until errors like those happened.When writing an essay, people often encode their knowledge and socio-cultural backgrounds.Hence, S007 and S009 reasoned that students would make redundant mistakes because of the nature of Vietnamese culture and literature.As for the error omission, S001, S003, and S008 said that forgetting to proofread or forgetting specific words was the root cause for this segment.Lastly, interviewees gave various responses to the overabundance error type.Some, like S005 and S002, suggested that time pressure does not offer students the luxury to think, so they often repeated the same word to finish on time.Others, like S010 and S004, mentioned that confusion between written and spoken forms can lead to these mistakes, as spoken language tends to be more forgiving regarding the repetition of words or ideas.Most answers, however, highlighted that insufficient vocabulary and/or grammar is the main reason for overabundance.

Illogical order
Four interviewees suffered coherence inaccuracies through the logical order criteria.As a result, they were asked an additional question about mishap.Surprisingly, their answers were similar.S007 and S008 shared that because of their writing style, they were more suited to describing ideas through importance and deductive means, so they neglected the other logical orders.S009 mentioned that they were highly influenced by their L1 writing requirements, describing them as primarily deductive and significant in their writing process.As for S010, they suggested critical thinking to be their obstacle.They pointed out that they were not familiar with brainstorming, creating bad habits, which led them to have little choice in arranging their ideas.
Moving forward, the participants were then asked why they struggled with the logical order criteria and its types, using it wrongly or sparingly.Only one person did not provide an answer to this question, stating that they could not think of anything significant; other than that, the remaining nine volunteers all shared their insights on the matter.S001, S002, S003, and S005 shared a common perspective.They believed that students were not used to different types of logical order.As a result, learners tended to stick to what they were most comfortable with and would shy away from experimenting with newer elements.Another point that the participants made, in coordination with the previous statement, was when students write a topic, they generally do not think about multiple aspects and thus only use a handful of ways to organize their essay.The fear of making errors was a different opinion on why this might happen, and it usually held learners back (S005, S007, S010).
A special case in this interview is S006.He produced a short essay (about 230 words) without major flaws in cohesion or coherence.He did not focus much on the specific criteria but mapped out the entire essay.He explored this approach to help him select the right words and structure his writing appropriately.

Lexical Cohesion
The results showed three main devices used: reference, conjunction, and lexical cohesion.Lexical cohesion had the highest error rate, followed by conjunction and reference.Generally, the study has determined that the number of cohesive instances (5472, see Table 3) contributed about 22.8% of the total word count (24,000).This finding contradicted several results that examined the cohesive devices used by L2 English students (Bui et al., 2022;Rahman, 2013).Their findings suggested less; about 7% of the word count was cohesive devices.As established earlier, across 80 essays, the most preferred cohesive device were lexical cohesion.Upon closer inspection, the students mostly used repetition and synonyms for their essays (see Table 8).Other studies also reinforce this notion, stating that English learners relied heavily on lexical cohesion in their writings (Kafes, 2012;Rahman, 2013).Specifically, Kafes' (2012) data pointed out that repetition was the primary device that the students used.Mojica's study (2006) also concluded that repetition was used abundantly compared to other types of lexical cohesion.
However, apart from repetition, many feasible ways can diversify an essay while building cohesion.Rahman (2013) supported the statement and suggested that repetition is a popular choice for non-native students, while other devices were extremely neglected.A great portion of errors fell into the overabundance kind and a near identical ratio for both misuse and redundancy mistakes.The number somewhat coincided with Bui et al. (2022), revealing that overabundance was most frequent for lexical cohesion.Lacking vocabulary is a common problem for many foreign language learners.Since they do not possess many words to express themselves, repetition tends to arise.Another reason could be time pressure, as an essay lasts for 40 minutes only.

Reference
Another detail is that students mainly use reference, conjunction, and lexical cohesion while evading the other remaining two types (see Table 6).This aligned with the studies by Bui et al. (2022), Rahman's (2013), and Yang and Sun (2012).As mentioned, lexical cohesion was used the most, followed by reference and conjunction.This high density could be attributed to the students' familiarity with these devices; this fondness, however, does not translate to better proficiency.
In other words, more cohesive devices do not guarantee higher cohesiveness since writers could risk potential errors.Yang and Sun's (2012) concluded that although sophomores (lower proficiency) produced more cohesive ties, their quality was not compared with their senior counterparts (high proficiency) due to inexperience.In the present study, students casually used personal references (i.e., you, I, they) in large quantities, indicating their familiarity with the device.The high density of references caused students to fumble in the misuse and redundancy categories, making the essay akin to that of oral discourse.

Conjunction
Although implemented plentifully, the conjunction was utilized the least (except for substitution and ellipsis) among the three devices (Bui et al., 2022;Rahman, 2013;Yang & Sun, 2012).Its error types revealed some struggles that students might encounter when writing essays.Data collection suggested students' problems using the correct conjuncts and/or placing one appropriately.Stated by Oanh and Huynh (2023), students might not fully understand the grammatical knowledge of conjunctions to use them properly.
Regarding substitution and ellipses, data analysis suggested that the two devices were surprisingly underused.This finding aligned with Bui et al.'s (2022) study, in which almost no substitution or ellipsis were in their data.The reason for such shortcomings could be that students do not quite grasp the concept of these two devices.Has (2021) proposed that the overuse of reference might be due to its similar function to substitution.Since students are less familiar with substitution, they tend to rely more on references.Substitution and ellipsis are generally features of spoken language, making them less suitable for written tasks compared to reference, conjunction, and lexical cohesion.Because of the low usage of these two methods, they are also the least problematic area for students.

Coherence Analysis
Data analysis has picked up on various coherent devices used to support ideas and make sense of the words written.The results show that 33.19% are repetition, differing greatly from Has' (2021) findings.The opposition trend continued with both pronouns and transitional links.The researchers recorded 25.30% and 23.90%, respectively (see Table 5), while Has (2021) documented fewer for the two criteria (13.85% and 16.54%, respectively).Admittedly, the researchers judged only personal pronouns (he, his, she, her, it, they, them, you, I) as they deemed that those pronouns if used consistently, can construct a steady narrative and coherence.
The logical order is the unique element in this criterion.There are several ways to organize one's essay, such as chronological order, importance order, or contrast order.Because the essay's type gives opinions, the researchers have chosen four order kinds: importance, contrast, deductive, and cause-effect, to act as special arrangements in essays.Each type of order has a specific set of keywords that the researchers used for identification.Moreover, the researchers determined that each sentence could act in logical order if it supports the preceding sentence and contains the necessary keywords.
To begin with, logical order helps the writer express their ideas clearly.Words like "first," "second," and "lastly" show the order of importance.Contrast is used to show differences between ideas; words like "however," "although," and "on the other hand" are common for this purpose.Deductive or general to specific order involves starting with a general idea and then providing details; phrases like "for example," "for instance," and "as an example" indicate this order.Cause-effect type explains the relationship between two things, where one is the cause and the other is the effect, including "because", "since", "thus," and "as a result."For analysis, a logical order is considered incorrect if it misses its keywords or if a sentence does not support the main topic or previous ideas.Usually, these indicators are transitional links or conjunctions.

The reasons for making errors
Below are examples illustrating different types of logical orders and their errors in practice.These examples demonstrate the importance of contrast, deduction, and cause-effect relation in that order.
In terms of the order of importance, student S8 was trying to list possible characteristics of selfemployment.The word "another" is one of many keywords for this type of order as it gives people clues that there are more important ideas before this sentence.The next sentence immediately caused confusion as it missed a necessary word.The first and second sentences were not linked, appearing as separate statements.Consequently, the student wanted to list the next reason in their argument yet failed to include a correct conjunct.This mistake, even small, could create confusion for readers.
... Another difficulty that I face when starting a business is that the competitive market is very harsh from large and small businesses to large corporations.(...) I have a mastery mindset, dare to think, and dare to do, have a great ambition to dream ..

. [S8]
Regarding contrasting order and its blunder, despite using an appropriate link, their reasons were confusing to read through and did not fully explain the original statement.One can read through the sentences and piece out what the writer meant.However, the idea was poorly delivered, causing a poor reading experience and a difficult analysis experience.... For example, now, instead of choosing to work in companies or factories, young people choose to do business, such as opening a clothing store, coffee shop, milk tea shop, or online business.But they just thought about it at first and didn't think the long-term, because nowadays many people also have self-employment thoughts, so the selfemployed business is expanding and popular everywhere, so after a while, many shops had to temporarily close their operations and have to apply for jobs … [S43] The statement below is another example of the contrasting category.The student gave an opinion on the advantages of self-employment and supported that statement by describing the disadvantages of contracted labor.Yet, they mistakenly used the wrong transitional link.Upon reading the sentences, a reader can point out this anomaly and know that the writer made a mistake.... For example, if I have my own job or sick days while working, I can take time off work without asking anyone's permission.And when working at the company, I have to write an email to ask for permission and have my salary deducted ..

.[S6]
The next issue was the deductive logical order.The research underlined a few words that indicated an example being given.The paragraph's goal was to draw out several advantages of freelancing.Their main points for the paragraph were flexible schedules and flexible career choices.The examples to support these points, however, were puzzling to decipher.Overall, the sentences could be understood with some effort, but the poor organization made its deductive function fall short.The next two examples were no better than the first.
Finally, the excerpt below illustrates the cause-effect relationship.In these sentences, the learner wanted to conclude that working alone is not always a good choice.However, they missed a connective in the final sentence.The overall meaning was not impacted, but most people would understand the message but a somewhat strange literary engagement.
... Being self-employed has certain drawbacks, such as not having enough time to accomplish the things you want to do or feeling nervous most of the time since you must do everything by yourself.(...) Working alone may not always be the best option. [S41] As the result states, logical order error was rated highest.The small analyses above explained a couple of common mistakes that many students made in the data set.The mistakes included missing and/or wrong conjunctions, lack of support for the original idea in sentences, poor idea organization, and meaning that might make sense.
To gain further insight into the reasoning behind the mistakes, the researchers interviewed 10 students, labeled S001 to S010.The previous section summarized the results, so this section highlights some notable responses.
The researchers identified specific instances where S001 misused words.
Yeah, (awkward laughing) I made that mistake because I was careless.I wrote too fast and used it wrong.As for the second one, it's been so long since I use it, I forgot its meaning back then….well, it is a bit silly, but, like I said, I wrote my essays too fast.In the end, I forgot to recheck it so I must have forgotten those two conjunctions. [S001] The participant forgot some important conjunctions and made careless use of a word.Moreover, he admitted to failing to remember the second word and wrote the wrong word, rushing to meet the 40-minute duration.
Some interviewees expressed similar views regarding overuse mistakes.For example, S009 committed two cohesion mistakes: redundancy and overabundance.For overabundance, poor vocabulary repeatedly came up during the interview as the main reason.However, regarding their redundancy, S009 said an interesting idea: that the nature of Vietnamese literature causes him trouble with English in general and redundancy in specific.He went on to explain that the writing requirement from L1 had taken root in their mind that now "it is an auto-pilot reaction".
For overabundance, I can say that I still have limited lexical items and expressions, so I almost always make this error.For redundancy, because of the influence that I got from Vietnamese literature, which requires you to write complex words in a sentence.So, I think that, when trying to apply it to English writing, it can cause some unwanted words.
[S009] Furthermore, they exhibited three problems with their cohesion usage.They tried incorporating as many complex structures and words as possible to ensure their essay did not appear dull.For this point, Hung (2022) concluded that this way of writing is a common misconception among Vietnamese students.
About redundancy and omission, I think it because it's been a long since I last wrote an essay.It's been a long time since I utilized these complex words and structures, so I guess I forgot a few things here and there.Also, when I wrote the essay, I wanted to use a variety of different structures so the essay wouldn't be boring to read.[S008] Overall, the interviews revealed valuable information regarding the four types of cohesion errors.Limited vocabulary seemed to be the main reason for the participants' misuse and overabundance, while omission and redundancy had some surprising factors.Omission can be attributed to rushing and forgetfulness, and redundancy can be linked to students' Vietnamese writing styles.
The essays applied all 4 kinds of logical order quite equally.However, the students also made plenty of errors; for instance, S007 claimed that his way of presenting ideas can be confusing to many, plus a personal negligence to written skills.

I generally don't focus much on organizing since I am not good at literature, and I don't really plan on improving that. Another reason could be due to my way of explaining things. I intend to say (or write in this case) what comes to mind, and I usually use a lot of examples to refer to things. [S007]
In an interview with S010, she argued that limited brainstorming can reduce the various types of logical order in written English.Moreover, she shared that the fear of speaking her mind made her have less vocabulary than desired.

I have a bad habit of ignoring critical thinking and just answering quickly and briefly to be done with it. This made me rarely think profoundly about different aspects of a problem/topic, and I'm quite ashamed of this. I also have the fear of saying the wrong thing or using the wrong word because I don't want to be criticized by others. [S010]
In sum, the students used plenty of lexical cohesion, reference, and conjunction as cohesive ties in their writings.Lexical cohesion, notably repetition, was the most common, followed by reference and conjunction.Their errors mostly resolved around misuse and redundancy categories, with a few exceptions.Substitution and ellipses were shockingly underrepresented; thus, the researchers did not record any mistakes in those devices.Furthermore, more coverage does not mean higher proficiency; students may be more familiar with the devices and opt for them more frequently.The reasons for the errors can come from time pressure, unfamiliarity, and lexical resources.
Regarding coherence, the research focused on how well students organized their ideas logically and found that this was where most mistakes happened.Interviews with students confirmed these findings and added some new insights.The interviews highlighted issues like different writing styles, first language (L1) influences, the importance of brainstorming, and personal carelessness.

Summary of the Study
This study examined the errors regarding cohesion and coherence in the essays written by English majors.Employing a mixed-methods approach, the researchers analyzed 80 essays to identify errors in these fundamental aspects of writing and conducted 10 interviews to explore their underlying reasons.The study found that lexical cohesion, including repetition and synonymy, was the most frequently used cohesive device but also had the highest error rate.Common errors included misuse, redundancy, and overabundance of cohesive devices.Furthermore, the logical order was the most problematic criterion for coherence, with many students struggling to organize their ideas logically.Errors in the use of transition signals and consistent pronouns were also noted.The researchers also revealed several reasons for the errors, such as unfamiliarity with concepts of coherence and cohesion, limited vocabulary, overabundance, and illogical order, indicating that students face challenges in maintaining logical order and effectively using cohesive devices, with lexical cohesion presenting the highest error rate.These results emphasize the significance of cohesion and coherence in writing and provide valuable insights into areas where students may benefit from additional support and instruction.

Limitations of the Study
This research has several limitations.First, it was conducted at a private university, providing a limited and confined context for such a broad topic.Secondly, due to time constraints, the author utilized a data set of only 80 essays, which is insufficient for generalizing the findings to the larger population.Lastly, the research did not delve into the sub-types of cohesion.

Recommendations
The study's findings suggest several ways to improve students' writing skills, specifically focusing on cohesion and coherence.Firstly, teachers should develop interventions to enhance students' understanding and application of these concepts.The interventions can be workshops or seminars focusing on the concepts of cohesion and coherence, illustrating correct and incorrect usage.Moreover, teachers can build interactive lessons, including hands-on activities, or incorporate regular writing exercises focused on practicing specific cohesive devices and coherence strategies.
Secondly, regular assessment and feedback are crucial to monitor students' progress in these areas.Teachers should provide constructive feedback to help students address specific issues pertaining to cohesion and coherence in their writing.Teachers should demonstrate how to use cohesive devices to connect ideas and improve overall coherence.Beneficially, peer review activities can allow students to receive feedback from their peers and learn from each other's writing.Future research should explore longitudinal studies and cross-institutional comparisons to monitor progress and pinpoint common challenges.

Table 3
Frequency of Cohesion Use

Table 4
Types of Cohesion Errors