These are used to help form tenses of other verbs, and to show forms such as questions and negatives.
Must, can, should, might, will, and would are examples of modal auxiliary verbs. They 'help' other verbs, but unlike do, be, and have, they have their own meanings. For example, must expresses obligation; can expresses ability.
These are all the other verbs in the language, for example play, run, help, think, want, go, see, eat, enjoy, live, die, swim, etc.
Do, be, and have can also be used as full verbs with their own meanings.
| Verb | As full verb | Example |
|---|---|---|
| do | perform an action | I do my washing on Saturdays. |
| be | exist / state | We are in class at the moment. |
| have | possess | They have three children. |
Be + verb + -ing is used to make continuous verb forms which describe activities in progress and temporary activities.
He's washing his hair. (Present Continuous)We were watching TV at 9.00. (Past Continuous)I've been learning English for two years. (Present Perfect Continuous)Be + past participle is used to form the passive.
Paper is made from wood. (Present Simple passive)My car was stolen yesterday. (Past Simple passive)The house has been redecorated. (Present Perfect passive)Have + past participle is used to make perfect verb forms.
He has worked in seven different countries. (Present Perfect)She was crying because she had received some bad news. (Past Perfect)To make a negative, add -n't to the auxiliary verb. If there is no auxiliary verb, use don't/doesn't/didn't.
| Positive | Negative |
|---|---|
| He's working. | He isn't working. |
| I was thinking. | I wasn't thinking. |
| We've seen the play. | We haven't seen the play. |
| She works in a bank. | She doesn't work in a bank. |
| He went on holiday. | He didn't go on holiday. |
It is possible to contract the auxiliaries be and have and use not.
He's not playing today. (= He isn't playing today.)We're not going to Italy after all. (= We aren't going to Italy…)I've not read that book yet. (= I haven't read that book yet.)To make a question, invert the subject and the auxiliary verb. If there is no auxiliary verb, use do/does/did.
| Statement | Question |
|---|---|
| She's wearing jeans. | What is she wearing? |
| You were born in Paris. | Where were you born? |
| Peter's been to China. | Has Peter been to China? |
| I know you. | Do I know you? |
| They didn't go out. | Why didn't they go out? |
There is usually no do/does/did in subject questions (when there is no new, different subject introduced after the question word).
Who wants ice cream? What flavour ice cream do you want?Who broke the window? How did you break the window?Short answers are very common in spoken English. If you just say Yes or No, it can sound rude. To make a short answer, repeat the auxiliary verb. In the Present and Past Simple, use do/does/did.
| Question | Short answer |
|---|---|
| Are you coming with us? | Yes, I am. |
| Have you had breakfast? | No, I haven't. |
| Does she like walking? | No, she doesn't. |
| Did Mary phone? | Yes, she did. |