What are auxiliary verbs?

What are auxiliary verbs?

Besides acting as the main verb of a sentence, verbs are also helpful in a number of other ways, which are not so obvious. There are also auxiliary or ‘helping’ verbs that are used in a variety of ways. The main auxiliary verbs are be, have and do.

They are used with main verbs to make specific tenses:

  • He is coming. present continuous
  • She wasn’t driving. past continuous
  • We haven’t seen an eclipse before. present perfect
  • She had dropped her keys. past perfect

The verb be + a past participle is also used to make passive forms:

  • The road is mended once a year.
  • The engines are made in Germany.
  • The votes are being counted in the hall.
  • The whales had been driven onto the shore.

The auxiliary verbs are used to make questions:

  • Do you want a drink?
  • Don’t you like opera?
  • Have you finished the work yet?
  • Which train do you think you’ll catch?

Auxiliary verbs are used to make exclamations:

  • Wasn’t she awful!
  • Haven’t you grown!
  • Didn’t they do well!
  • Isn’t it freezing!

To make questions tags:

  • We’re very happy, aren’t we?
  • It’s cold, isn’t it?
  • You don’t like fish, do you?
  • You haven’t had a happy childhood, have you?

Note that the verb to be is the most common verb in English and it is the only one that can operate as both a main verb and an auxiliary verb. It doesn’t need any additional help to make questions or negatives.

  • I am very happy.
  • Am I very happy?
  • I’m not very happy.

Compare this with the verbs do and have which need additional help to make questions and negatives.

  • I have a very large nose. I don’t have a very large nose.
  • I do my piano practice at 6 o’clock. I don’t do my piano practice.

What’s a modal auxiliary verb?

They are also ‘helping’ verbs because they are used to express a range of meanings, such as certainty, probability, possibility, suggestion, permission, instructions, requests, obligations, necessity, ability and so on. The main modal auxiliary verbs are:

  • can, could, may, might
  • shall, should, will, would
  • must, ought, to
  • also need to be able to, have (got) to

The main types of use of modal auxiliary verbs

certainty / probability (must, will, ought to, can’t, should)

  • He must be feeling very unhappy at the moment.
  • She ought to forget him, and move on.

possibility (may, might, could, can)

  • She might arrive on the 5 o’clock train.
  • They may come on Sunday, but I’m not sure.

suggestion (may, could, shall, might)

  • Shall we start again?
  • You may want to read over your essay again.

permission (may, can, could)

  • Can I connect this wire now?
  • You may begin the examination.

instructions and requests (would, will, can, could)

  • Can you explain that in words of one syllable?
  • Could you close the door, please?

obligations / necessity (must, have to, have got to)

  • I must send my mother a card on her birthday.
  • I’ve got to re-write this essay.

ability (can, could, be able to)

  • I couldn’t stop laughing!
  • He won’t be able to shift that stone.