The modal verb may is used with a bare infinitive to express the idea that something is possible or permitted. It is also used to express opinions and wishes.
Might is the past tense of may, but has a number of other meanings.
| Present Tense | Past Tense |
| He says he may come. I know there may be no-one there. ’The story may be true,’ he said. ‘May I have another biscuit?’ He asked. | He said he might come. I knew there might be no-one there. He said the story might be true. He asked if he might have another biscuit. |
Asking for or Giving Permission
May is used to ask for, give or refuse permission.
- ‘Please may I open a window?’
- ‘Yes, of course you may.’
- Users of this software may modify their copy of this program or any part of it.
- No part of this publication may be reproduced without the prior permission of the publisher.
- May I make a suggestion?
If you want to be a little more polite or formal in making a request, use might:
- I wonder if I might open a window?
- Might I have a quick word with you?
In reported speech, might is rather formal and a little old-fashioned:
- He asked if he might have another biscuit.
Could would be more likely in everyday speech:
- He asked if he could have another biscuit.
Note that although you can use might in this way to ask for permission, you can only use may to give permission:
- ‘I wonder if I might open a window?’
- ‘Certainly you may.’
May not is used to withhold permission or to state what is not allowed. It is mostly used when telling someone what they are not allowed to do, or in formal English, when stating rules and regulations:
- ‘Please may I leave the room?’ ‘No, you may not.’
- Children under the age of sixteen may not use this equipment.
- Users may not copy or modify this software except by permission of the distributor.
In everyday informal English, especially with the pronoun I, it is more natural to use can’t, not be allowed to, etc:
- I can’t come to the pictures with you tonight.
- I’m not allowed to go into town on my own.
May and might are sometimes used when expressing a polite or tentative opinion in a way that suggests you are asking permission to do so:
- That was a pretty stupid thing to do, if I may say so.
- And, lastly, may I say how much I appreciate all the hard work that has been done in this campaign.
- I consider this book to be the most informative and, might I add, the simplest to use of all the instruction manuals I have read.
Similarly, may is used when making a polite offer, especially an offer of help:
- May I help you?
- May we be of assistance?
Expressing Possibilities
May is used to suggest that something is possible, now or in the future.
- We may all be out of work by this time next week.
- She may find a way of persuading him to come.
- Be careful what you say. Some of these people may be journalists.
- We may go back to France again next year, but my wife may not want to.
- A new economic treaty may be signed soon.
- Don’t worry. We may not have to wait long.
- Your doctor may get the results of these blood tests by tomorrow afternoon.
When referring to the past, use may have:
- She may have left by now.
- A meteor may have caused dinosaurs to become extinct.
- The measles outbreak may have been started by someone bringing in the virus from abroad.
- That is a possibility you may have overlooked.
- You may have heard of her. She’s a famous poet.
May have is also used when you want to say that it is possible that something will have happened by some time in the future:
- She may have left by the time we arrive.
- We may have found the information we need before the meeting starts.
- I may have finished this by tonight.
- By this time next year, we may all have been out of work for months.
Might and might have are used to suggest possibilities that are less likely or less certain than those expressed by may and may have.
- We might all be out of work by this time next week.
- Take an umbrella with you. It might rain.
- That is a possibility they might have overlooked.
In talking about possibilities, яму and might are sometimes followed by well:
- We may well meet her at the concert.
- They might well have left by now.
Do not confuse this use of well with the phrases may as well and might as well. May as well and might as well are used to say that it would be sensible to do something or that there is no point in not doing it:
- Since I’m here, I may as well help you pack.
- If you’re going to be here till Friday, you might as well stay till Monday.
Might as well is also used to say that something would make no difference to some situation:
- He never notices me. I might as well be invisible.
- You might as well leave now. There’s nothing more you can do to help.
Might is used to talk about something that could happen in the future:
- If you asked him, he might lend you the money.
- If we set off right away, we might get there by lunch-time.
- I am hoping that we might visit my aunt while we are in Japan.
Might have is used to talk about something that could have happened in the past, but in fact didn’t happen:
- What on earth did you do that for?
- You might have been hurt! (but you weren’t)
- If you hadn’t interrupted me earlier on, I might have got this job finished by now. (but you did interrupt me, so I haven’t got it finished)
Might can be used in a slightly humorous or pompous way with virtually no meaning at all when you are asking for information:
- ‘And who might you be?’ asked the man with a sneer. (= who are you?)
- ‘And what might be the point of all these protests?’ (= what is the point of them?)
Making Admissions
May can be used to say that although one thing is true, something else is nevertheless also true.
- There may be other books on the subject, but this is still the best. (= although there are other books, this is still the best)
- He may be the boss, but his wife makes all the important decisions. (= although he is the boss, it’s his wife who makes all the important decisions)
- Calm as she may seem, I’m sure she is really a bundle of nerves. (= although she seems calm, I’m sure she is really very nervous)
Might can be used to say that although one thing is perhaps true, something else is nevertheless also true:
- You might think that was a clever thing to do, but I don’t.
Expressing Wishes
In rather formal English, may is used to express a wish or hope.
- May God forgive you for what you have done!
- May the Force be with you. [Star Wars]
- Isn’t the weather marvellous these days! Well, long may it last. (= I hope it lasts a long time)
- ’Tis (= It is) the star-spangled banner! О long may it wave O’er (= Over) the land of the free and the home of the brave. [from ‘The Star-Spangled Banner’, the national anthem of the United States]
Expressing Purpose
In formal English, may is used when you are giving the reason for doing something.
- My parents are moving back to England so that they may see more of their grandchildren.
- Please fill out the form below so that we may better understand your needs.
- Hile have also provided a search engine so that you may find and retrieve the documents you need online.
In this sense, the past tense is might:
- My parents moved back to England so that they might see more of their grandchildren.
Other Uses of Might and Might Have
Might is used to make suggestions:
- We don’t sell stamps, but you might try at the shop next door.
- If you want advice on buying a new computer, you might ask my cousin. She knows about these things.
Sometimes might and might have are used to make suggestions about what someone ought to do or ought to have done, in a way that shows that the speaker is rather annoyed:
- You might at least try to be polite to my mother!
- Well, you might have told me you were coming!
Might and might have are used to say that something is like something else:
- It’s so cold these days, it might be January rather than July.
- From the top of the hill, the cars looked so small that they might have been little insects.
When you say that you might have known or might have guessed something, you mean that it is something that could be expected to happen:
- You might have known she’d be late. She usually is.
- I might have guessed that you’d be here.
Note the tenses used in conditional sentences:
- If you ask her, she may help you
- If you asked her, she might help you.
- If you’d asked her, she might have helped you.