Cohesion

Cohesion refers to the linguistic devices that create connections between parts of a text, making it hang together as a unified whole rather than a sequence of unrelated sentences. The foundational taxonomy comes from Halliday and Hasan (1976), Cohesion in English.

The Five Types

Reference — using pronouns, demonstratives, and comparatives to point back (anaphoric) or forward (cataphoric) to something already mentioned or about to be mentioned. "The students completed the task. They found it challenging." Reference chains are the backbone of text continuity.

Substitution — replacing a word or phrase with a substitute form to avoid repetition. "I'll have a coffee. She'll have one too." Less common than reference but important in spoken English.

Ellipsis — omitting a word or phrase that is recoverable from context. "She can speak French and he can [speak French] too." Ellipsis is the zero form of substitution — the element is simply left out.

Conjunction — using [[Linking|linking words]] and phrases to signal logical relationships between clauses and sentences: addition (moreover), contrast (however), cause (therefore), time (subsequently). This category overlaps significantly with Discourse Markers.

Lexical cohesion — creating connections through vocabulary choice:

• Repetition — using the same word again
• Synonymy — using a synonym or near-synonym
• Hyponymy — using a superordinate or subordinate term (fruit → apple)
• Collocation — using words that habitually co-occur (hospital... doctor... patient... treatment)
• Meronymy — part-whole relationships (car... engine... wheel)

Lexical cohesion is the most frequent type in most texts and the one learners rely on most heavily, even when their grammatical cohesion is weak.

Cohesion vs. Coherence

This distinction is essential and frequently tested in language teaching contexts. Cohesion is textual — it lives on the surface of the text in identifiable linguistic features. Coherence is conceptual — it exists in the reader's ability to construct meaning from the text.

A text can be highly cohesive but incoherent:

The cat sat on the mat. However, photosynthesis requires sunlight. In addition, the French Revolution began in 1789.

Every sentence is linked by a conjunction, but the text makes no sense. Conversely, a text can be coherent with minimal explicit cohesion, relying on shared knowledge and logical sequencing.

Teaching Cohesion

• Text analysis — give learners a text and ask them to identify and classify cohesive devices; trace reference chains; highlight conjunctions
• Gap-fill with cohesive devices — remove pronouns, conjunctions, or synonyms and ask learners to restore them
• Text reconstruction — jumble sentences and ask learners to reorder them, discussing which cohesive clues helped
• Writing feedback — flag overuse of conjunctions (a common intermediate-level problem) and underuse of reference and lexical cohesion

Cohesion is a key assessment criterion in writing exams. IELTS Band Descriptors for Coherence and Cohesion explicitly evaluate the range and accuracy of cohesive devices. Teaching cohesion as a toolkit — not just "use [[Linking|linking words]]" — gives learners more control over their writing.