clause, and so + auxiliary + subjectUse this after a positive first clause. The auxiliary comes before the subject.
Ellipsis and Substitution
B2Ellipsis and substitution help you avoid repeating words. Use short patterns like so can he, neither do I, or do so when the meaning is already clear.
What you'll learn
- Show matching positive meaning with so ... or too.
- Show matching negative meaning with neither ... or either.
- Replace a repeated action with do so.
- Leave out a repeated verb after an auxiliary.
- Keep the same auxiliary pattern in the short second clause.
Structure
clause, and subject + auxiliary + tooThis version keeps normal word order. Put too at the end.
negative clause, and neither + auxiliary + subjectUse this after a negative first clause. Do not add another negative word after neither.
negative clause, and subject + auxiliary + not + eitherThis version keeps normal word order. Put either at the end.
subject + auxiliary + do soUse do so to stand for an action already mentioned.
clause, and subject + auxiliary + tooIf the main verb is already clear, the second clause can stop after the auxiliary.
Build a sentence
Auxiliary
Subject
She can swim,andsocanhe
She can swim, and so can he.
After so, put the auxiliary before the subject.
When to use
Same positive idea
When two people share the same positive statement, shorten the second part: She can swim, and so can he.
Same negative idea
When two people share the same negative statement, use neither ... or either: Tom doesn't drive, and neither does Lisa.
Repeated action
When the same action comes again, replace it with do so: Maria promised to email us, and she did so that evening.
Markers
sotooneithereitherdo socandidhas
Common mistakes
Wrong
She doesn't like coffee, and so do I.
Correct
She doesn't like coffee, and neither do I.
After a negative first clause, use neither ... or a negative clause with either, not so.
Wrong
Tom can cook, and so he can.
Correct
Tom can cook, and so can he.
After so, put the auxiliary before the subject.
Wrong
Lisa has finished the report, and so did Mark.
Correct
Lisa has finished the report, and so has Mark.
The short second clause must match the auxiliary pattern of the first clause.
Wrong
Anna promised to call, and she did call the next day.
Correct
Anna promised to call, and she did so the next day.
Do so replaces the repeated action and makes the sentence lighter.
Wrong
Maria has finished the report, and Tom has finished the report too.
Correct
Maria has finished the report, and Tom has too.
When the repeated verb phrase is clear, English often leaves it out after the auxiliary.
Common misconceptions
❝ After so, the word order stays normal: so he can, so she has. ❞
After so and neither, the auxiliary comes before the subject: so can he, neither has she.
❝ Clear English always repeats the full verb phrase. ❞
English often drops repeated words when the meaning stays clear, especially after auxiliaries.
Skills in this rule (5)
SO_CAN_TOOw5Use so + auxiliary + subject or subject + auxiliary + too to avoid repetition
When two people share the same ability, opinion, or action, replace the repeated words with so + auxiliary + subject or with too at the end.
NEITHER_DO_EITHERw5Use neither + auxiliary + subject or subject + auxiliary + not + either for matching negatives
When two people share the same negative meaning, use neither + auxiliary + subject or use either at the end of the second negative clause.
DO_SO_INSTEAD_OF_REPEATw4Use do so to replace a repeated action
After a verb has already appeared, use do so to refer to the same action instead of repeating the full verb phrase.
LEAVE_OUT_REPEATED_VERB_AFTER_AUXw5Leave out a repeated main verb after an auxiliary
When the auxiliary already shows the tense or modal, the repeated main verb can drop if the meaning is clear from the first clause.
CHOOSE_MATCHING_AUXILIARYw5Choose the auxiliary that matches the first clause
The short second clause must keep the same auxiliary pattern as the first one: can with can, do with do, did with did, has with has.