Ellipsis and substitution
Leave out or replace repeated words accurately, using auxiliaries, so, not, one and do so.
20 minProficiency
1The grammar
Ellipsis leaves out words that can be understood; substitution replaces them with a short form. After an auxiliary, the rest of the verb phrase is often dropped: 'She said she would resign, and she did.' Clause-final forms of 'be', 'have' and modals are not contracted: 'He isn't a lawyer, but I am', not 'but I'm'.
'So' replaces a positive clause and 'not' a negative one after think, hope, believe, suppose, expect and be afraid. With 'hope' and 'be afraid', only 'I hope not' and 'I'm afraid not' are used for the negative. With 'think', 'I don't think so' is the usual negative, while 'I think not' is formal. 'Do so' replaces an action, usually in formal writing: 'The firm was told to withdraw the claim, and it did so.'
'One' and 'ones' replace countable nouns, not uncountable ones: 'the senior ones', but 'recycled paper rather than new paper'. In a to-infinitive, the verb can be dropped but 'to' stays: 'She had hoped to attend, but she was unable to.'
Gapping leaves out a repeated verb in a second clause: 'One report went to the ministry and the other to the regulator.' In British English, 'do' can also follow an auxiliary: 'Will you attend?' 'I might do.' American English normally uses 'I might.'
2Structure and formation
Post-auxiliary ellipsis
subject + auxiliary (rest of verb phrase omitted)
He promised to apply, and he has.
Gapping
clause + and + subject + complement (verb omitted)
The first witness spoke for an hour, the second for ten minutes.
Clausal substitution
think / hope / be afraid + so or not
Is the decision final? I'm afraid so.
Action substitution
do so
She was asked to apologise, and she did so.
Nominal substitution
adjective + one / ones
The older models are slower than the new ones.
3Examples
The first witness spoke for an hour, the second for ten minutes.
The verb 'spoke' is omitted in the second clause.
Ms Park has read the report, and so has her deputy.
'So' + auxiliary + subject repeats the positive idea.
The junior doctors accepted the offer, as did the nurses.
'As' + auxiliary + subject is a formal alternative to 'and so did'.
Is the decision final? I'm afraid so.
'So' replaces 'the decision is final'.
The court ordered the firm to pay, and it did so within a week.
'Did so' replaces 'paid'.
We asked for a larger room, but there wasn't one available.
'One' replaces 'a larger room'.
4Common mistakes
He isn't a shareholder, but I'm.
He isn't a shareholder, but I am.
An auxiliary or 'be' at the end of a clause is not contracted.
I don't hope so.
I hope not.
The negative of 'I hope so' is 'I hope not'.
The firm prefers recycled paper to new one.
The firm prefers recycled paper to new paper.
'One' replaces countable nouns only, and 'paper' here is uncountable.
The minister wanted to resign, but she was not able.
The minister wanted to resign, but she was not able to.
When the infinitive verb is dropped, 'to' normally stays.
5Practical usage
Cohesive writing
Ellipsis and substitution avoid repetition and make connections clearer. 'Do so' and 'as did' are especially common in formal writing.
Natural conversation
Short replies such as 'I'm afraid so', 'I hope not' and 'She might' sound more natural than repeating the whole clause.
Now practise it
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