Cohesion vs. Coherence: Untangling the Knot

Cohesion and   coherence. They are often used interchangeably in everyday staffroom chat So what is the difference? In short:

• Cohesion is the network of surface-level linguistic links that connect sentences and clauses (e.g., pronouns, conjunctions, lexical chains).
• Coherence   is the underlying logical flow that makes the relationships of ideas evident and meaningful to a reader or listener.

A text can be beautifully cohesive yet completely incoherent. Conversely, a text can be coherent despite having few or no explicit cohesive devices.

Consider the following pairs of sentences:

1.  “My grandmother gave me a watch. It stopped working after a week.”   This is both cohesive (it refers back to the watch) and coherent (the second sentence logically follows the first—the watch was faulty).
2. Now look at this example (adapted from a classic linguistics exercise): “My grandmother gave me a watch. I like to eat apples on Tuesdays.”  Here, we have no cohesive tie between the sentences. Without any linking device or shared lexis, the text is both incohesive and incoherent—it feels random.
3. “My grandmother gave me a watch. That kind of sentimentality often skips a generation.” There is a cohesive tie (that refers back to the act of giving the watch), but is the text coherent? A reader might struggle to see the logical connection between receiving a watch and a generalisation about sentimentality skipping a generation. It is cohesive, but not coherent.

Problems with cohesion

1. The “Connector-Overuser” A sample from learner writing (B2 level, exam class):

“Firstly, social media has many advantages. However, it also has disadvantages. Moreover, young people spend too much time online. Therefore, parents should set limits. Furthermore, schools should teach digital literacy.”

Comment: This paragraph is packed with cohesive devices— firstly, however, moreover, therefore, furthermore . On the surface, it looks cohesive. But is it coherent? The logical connections are weak. Why does “young people spend too much time online” lead to “parents should set limits”? The argument jumps without development. This is a problem often caused by teachers who drill the idea of using cohesive devices in their learners (because they think it looks good in an exam) but do not work on helping the learners generate ideas and consider the logical relationships/connections between these ideas. This issue is often. jokingly, called “the FCE writing syndrome”.

How to deal with it:

• Instead of simply removing some or all the connectors, ask the learner:  What is the logical relationship between each sentence? Does each connector accurately reflect that relationship?  Often, learners discover they have used  therefore  as a default “next point” marker rather than to signal a genuine cause-effect relationship.

• Show learners two versions of the same text: one with minimal number of cohesive devices (but clear and concise) and one artificially loaded with  however, therefore, in addition (which does not make any sense). Ask them to decide which is more effe

  ctive and why. This builds critical awareness of register-appropriate cohesion.

2. Missing or Incorrect Referent

  Learner writing (B1 level, narrative):

“I went to the park with my friend. He was very crowded. It was difficult to find a place to sit.”

Comment: Here, the cohesive device  he  should refer to  my friend , but the meaning clashes—a person is rarely “crowded.” The intended referent was  the park . The learner has used reference incorrectly, creating a cohesive tie that undermines coherence.

How to deal with it: Use a simple reformulation task. Ask the learner to read the text aloud and identify who or what each pronoun refers to. Then provide a model:  “I went to the park with my friend. The park was very crowded. We found it difficult to find a place to sit.”  This draws attention to how accurate reference supports both cohesion and coherence.

3. Lexical Cohesion Without Logical Flow

  Learner writing (C1 level, opinion essay)

“Climate change is an urgent issue. The issue requires global cooperation. Global cooperation has been

 attempted many times. Many times, these attempts have failed. Failure is not an option.”

Comment: This text demonstrates strong lexical cohesion— issue, global cooperation, many times, failure —each repeated or chained to the next. Yet the overall argument is circular. The text repeats itself without progressing.

How to deal with it: Introduce the concept of  lexical chains  (recurring semantic links) and ask learners to map them visually. Then ask:  Does each sentence add new information, or are we cycling through the same ideas?  This shifts learners’ focus from “using sophisticated vocabulary” to “developing an argument.”

Classroom Activities for Teaching Cohesion and Coherence

    Activity 1: Scrambled Texts 

Take a short paragraph (6–8 sentences) and cut it into strips. In pairs, learners reassemble it. First, give them a version with clear cohesive devices (pronouns, repeated lexis, conjunctions). Then, give them a second text with those devices removed. In the debrief, introduce the terms  cohesion  (the clues they used) and  coherence  (the logic they inferred). This works well with levels B1 and above.

    Activity 2: Connector Bingo

Create a bingo card with cohesive devices ( however, therefore, this, these, in addition, for example ). As learners read a model text, they mark off devices they find. Then, in pairs, they discuss:  Which devices are essential to the meaning? Which could be removed without losing clarity?  This encourages critical evaluation rather than uncounted imitation.

    Activity 3: Cohesion-Free Writing Challenge

Ask learners to write a short paragraph (e.g., instructions for a recipe or directions to a landmark) without using any pronouns or conjunctions  . They quickly realise how unnatural this is. Then, ask them to rewrite it naturally and compare the two versions. This highlights the functional role of cohesive devices in a memorable, discovery-based way.

    Activity 4: Diagnosing Peer Writing

After learners have written a first draft, pair them up with a simple checklist:

• • • Circle all pronouns. Can you identify what each refers to?
    • Underline all connectors. Does each accurately show the logical relationship?
    • Highlight repeated key words. Does the text progress, or does it repeat the same idea?
    • This peer feedback task builds metalinguistic awareness and reduces the teacher’s correction load.

Postscript
Ιf you are studying for your DELTA course, you might want to read an amended version of this post on our DELTA blog with notes relevant to your study of the different modules

Further Reading:

•  Halliday, M. A. K., & Hasan, R. (1976).  Cohesion in English . London: Longman.
•  Cambridge Delta Module 1 past paper chief examiners’ reports (available via your course centre).
•  Thornbury, S. (2005).  Beyond the Sentence: Introducing Discourse Analysis . Oxford: Macmillan.