The Modal Verbs - May and Might

May and might are both common modal verbs. Here are a few important rules for modal verbs:
  • Modal verbs do not take any endings like -s, -ed or -ing
  • Modal verbs are followed by the base form of another verb (may do, might be)
  • Modal verbs make questions by inverting the subject and the modal verb (may I)
POSSIBLITY
Both may and might can be used to express possibility. Some examples:
  • It might rain tonight.
  • She might not come to the meeting.
  • I may need your help on this project.
  • He may be waiting for us.
Negatives:
  • The negative form of may is may not + base form. We never use a contraction for this negative. (You might find the word mayn’t in a dictionary, but it is not used.)
  • The negative form of might is might not + base form. The contracted form (mightn’t) is not used in American English, but it is used in British English.
Questions:
  • When may is used in a question, it refers to permission. See the explanation of permission below.
  • Might can be used in a question about possibility.
    • Might it rain later? (This form is not used in American English.)
    • Do you think it might rain?
May and might in the past:
The past form is may/might + have + past participle.
  • I might have left my phone at home.
  • She might not have seen my email.
  • Where is Amanda? I think she may have forgotten about the meeting.
Do not confuse may be and maybe. Maybe is an adverb meaning ‘possibly’. It is usually used in the beginning of a sentence.
  • Maybe I will take a vacation next month.
  • Maybe it will rain. / It might rain.
PERMISSION
May can be used to express permission. This could be in the context of an adult speaking to a child or an authority speaking in a formal context.
  • You may have a cookie after you finish your dinner. (adult to child)
  • You may now begin your exam. (professor to students)
Questions:
May can be used in a question to ask permission. The subject is usually first person singular or plural (I or we). May is considered more polite than can.
  • May I borrow your pen?
  • May I use your restroom, please?
  • May we come in?
In British English, might can also be used to ask permission.
  • Might I borrow your pen?
Note that we don’t use may to ask another person to take an action, so you cannot say “may you”. If you want to make such a request, you can ask “can you”, “could you” or “would you”.
  • Could you please turn down the music? I’m trying to study. (NOT: May you please…)
  • Would you help me clean the house? (NOT: May you help me…)
Students often ask:
When may and might are used for possibilities, is there any difference between them? Like may is a 50% possibility and might is a 70% possibility? Answer: No, there is no difference like this. They are equal in terms of possibility.