Explanation and Use
The auxiliary verbs are
- to be
- to do
- to have
To be
It is used to make continuous verb forms with verb + -ing
- They were reading.
and the passive with the past participle
- These books are printed in New York.
To do
We use it in the Present Simple
- Don't you want to go out tonight?
and in the Past Simple
- Where did you go on holiday?
We also use it to emphasise the sentence, giving extra force to the main verb
- A - "Can I buy lottery tickets here?"
B - "Well, we do sell them, but we haven't got any at the moment" - I do like planning my summer holidays in advance!
To have
It is used with the past participle to make perfect verb forms
- Have you ever been to Spain?
- When I arrived at the station my train had already left.
- Next year I will have been working for IBM for 15 years.
Avoiding Repetition
Auxiliary verbs can be also used in different situations:
1. In short answers, to avoid the repetition of the main verb:
- A - "Are you going to read that book?"
B - "No, I am not (going to read that book)." - A - "Did you have a nice meal?"
B - "Yes, I did (have a nice meal)." - A - "Have you managed to finish the job?"
B - "No, I haven't (managed to finish the job)."
2. In question tags:
- You are very depressed, aren't you?
- Do you understand what I say, don't you?
- You haven't been to China, have you?
3. To comment on given information: we make comments in conversation but avoid repeating information that has just been given. To reply questions: we use it to show that we are interested and paying attention to what is being said.
- A - "My sister is coming."
B - " I know she is." - A - "Jane doesn't like walking in the mountains."
B - "I thought she did!" - A - "My vacation was really awful!"
B - "Was it? I'm very sorry..." - A - "To celebrate your birthday, I've bought you a present"
B - "Have you? You are so nice!"
It is also possible to respond with a different auxiliary. To know which auxiliary verb to use, we must reconstruct the part of the sentence that is missing and consider the meaning and the time of the events in the sentence itself.
- A - "I didn't see the film."
B - "Oh you should have (seen the film). It was really great!" - My children always let me know what time they expect to be back. If they didn't (let me know), I would always be worrying about where they were.
- A - "I never see Martin these days. How is he?"
B - "We often do (see him). He is fine."
When there is more than one auxiliary, we can either use one or more in our answers.
- A - "He could have been lying."
B - "Yes, he could" or "Yes, he could have." or "Yes, he could have been." - A - "Would I have enjoyed the party?"
B - "No, I don't think you would" or "No, I don't think you would have."
Other Auxiliary Verbs - Modals
Modal Auxiliary Verbs are different from 'To Be', 'To Do' and 'To Have' because they have their own meanings. They are:
| can | could | may | might | will | would |
| shall | should | must | ought to | need |
They are auxiliary because they 'help' other verbs, defining the meaning of the sentences according to the context.
- Can you help me now? (= REQUEST)
- She can't have go my letters. (= PROBABILITY)
- He must be at least 80. (= PROBABILITY)
- You must fasten your seat belt. (= OBLIGATION)
- If you want, I will help you. (= WILLINGNESS)
- Listen, the doorbell is ringing, that will be the postman. (= PROBABILITY)
