Cohesion: the essentials

What is cohesion?

Cohesion refers to the way ideas are linked together to make meaning and applies to both written and spoken language.

For example, look at the sentence and focus on the words in red and black.

John came into the house, walked through it and went into the garden where he picked two red roses and a yellow one.

The words in red are examples of cohesion in English and they link to the words in black. it refers to the house, and links the two actions, where links the garden to the action, one at the end tells us it's also a rose so we don't need to repeat the noun. We don't repeat John in walked through it because we know who did that so we can leave out the word (that's called ellipsis or elision).

We can refer back in a text like this:

This is called anaphoric referencing.

It's also possible to refer forward in a text but that is rarer and gives a different, literary, feel sometimes.

This is called cataphoric referencing.

Types of cohesion

Reference:: Often this is achieved through the use of pronouns such as he in the sentence about John above. The pronoun refers either back or forward to the noun in sentences such as
    John didn't tell me where he is
    When she came in, I saw that Mary was very upset
Sometimes referencing is to a whole statement in examples such as
    As I mentioned earlier ...
    That is why ...
    This is what I said: ...
etc.
The use of referencing is the most common way to make texts hang together and it is widely used in both spoken and written language.
Here are some more examples:
    A: Where's the car
    B: I lent it to Mary?
    The bus broke down and that's why I'm late
When I finally got round to reading them, I thought the books were really good
Ellipsis:: This means leaving out (eliding is the technical term) a word because the reader / listener knows what the reference is. In the example above, we don't repeat John for the second verb. In spoken English, we very often get exchanges like
    A: What's for lunch?
    B: Cauliflower cheese (leaving out the clause, is for lunch)
Here are two more examples:
    A: Who arrived?
    B: John (eliding the verb, arrived)
    I don't like the red shoes but I love the blue (eliding the noun, shoes)
    He speaks good French and German (eliding the verb speaks and the adjective good because we assume they both apply to French and German)
For more, go to the guide to substitution and ellipsis linked in the list of related guides at the end.
Substitution:: In this, we don't leave out the word but change it for something more general. For example, above, the use of one to mean a rose or in something like
What wines do you want?
I'll take the French stuff
Conjunction:: We use conjunction to join ideas (see the section on conjunctions in the guide to word class, linked in the list at the end) in both spoken and written English. For example, and went into the garden, above, or in exchanges like
Why did you open the cage?
Because I wanted to change the water
Lexical cohesion:: This refers to the fact that in any text (written or spoken) there are likely to appear chains of related words. For example, in a text about hospitals it is likely that nouns such as medicine, patient, nurse, ward, treatment and doctor will appear along with verbs such as treat, admit, operate, sterilise and care for.
Grammatical cohesion:: This refers to the fact that we employ similar grammar in texts to keep the theme, especially the tense, consistent. For example
He went into the bar, walked up to the counter and ordered three beers
I will go to London and will see if I can see him

Here's an example of grammatical and lexical cohesion working together:

"While we were on holiday in a Spanish resort we used to go to the beach every morning and then we'd have lunch in a little restaurant in town where the tourists didn't go very much. The food was fantastic and very cheap and the fish dishes in particular were wonderful."

The tenses are consistently in the past (underlined), the nouns related to food and restaurants are also present (in red) and there's a second lexical string concerning holidays (in green). The text also contains examples of other forms of cohesion. Spot them.

Click to take a test on this area.

Related guides
deixis	for a much more technical guide considering how we talk about not here, not now and not me
substitution and ellipsis	for a more technical guide to these two areas
word class	the essential guide which includes consideration of conjunctions and more

Reference:
Halliday, MAK and Hasan, R, 1976, Cohesion in English, London: Longman.