The auxiliaries `be', `have', and `do' are used in forming tenses, negatives, and questions.
- The auxiliary `be' is used in forming the continuous tenses and the passive.
- The auxiliary `have' is used in forming the perfect tenses.
- The auxiliary `do' is used in making negative and question forms from sentences that have a verb in a simple tense.
1 The auxiliary verbs are `be', `have', and `do'.
The auxiliary verbs are used with a main verb to form tenses, negatives, and questions.
He is planning to get married soon.
I haven't seen Peter since last night.
Which doctor do you want to see?
2 `Be' as an auxiliary is used:
* with the `-ing' form of the main verb to form continuous tenses
He is living in Germany.
They were going to phone you.
* with the past participle of the main verb to form the passive
These cars are made in Japan.
The walls of her flat were covered with posters.
3 `Have' as an auxiliary is used with the past participle to form the perfect tenses.
I have changed my mind.
I wish you had met Guy.
Do not be confused with the fact that the present perfect continuous, the past perfect continuous, and the perfect tenses in the passive, are formed using both `have' and `be'.
- The reason for this is the fact that these tenses are formed by using the present perfect of the verb “be”, as in the following examples:
He has been working very hard recently.
All the doors in the house have been mended.
- or by using the past perfect of the verb “be”, as in the following examples:
They had been taught by an old teacher.
She did not know how long she had been lying there.
4 `Be' and `have' are also used as auxiliaries in negative sentences and questions in continuous and perfect tenses, and in the passive.
He isn't going.
Hasn't she seen it yet?
Was it written in English?
`Do' is used as an auxiliary to make negative and question forms from sentences that have a verb in the present simple or past simple.
He doesn't think he can come to the party.
Do you like her new haircut?
She didn't buy the house.
Didn't he get the job?
Note: you can use `do' as a main verb with the auxiliary `do' in the same sentence.
He didn't do his homework.
Do they do the work themselves?
You can use the auxiliary `do' with `have' as a main verb.
He doesn't have any money.
Does anyone have a question?
`Do' in affirmative sentences is only used for emphasis or contrast.
I do feel sorry for Peter.
WARNING: `do' is only used as an auxiliary with `be' in the imperative.
Don't be late!
Do be a good boy and sit still.
5 Some grammars include modals among the auxiliary verbs. When there is a modal in the verb group, it is always the first word in the verb group, and comes before the auxiliaries `be' and `have'.
She might be going to Switzerland for Christmas.
I would have liked to have seen her.
The auxiliary `do' is NEVER used with a modal.
- practice irregular verbs
- practice irregular verbs
- learn more about verbs which are not used in progressive/continuous forms (state verbs)