May vs. Might
May and might are both modal auxiliary verbs that express possibility. A modal auxiliary is a helping verb that expresses "modality," or the possibility, obligation, ability, or permission to perform an action. Some sources say that might is the past tense of may, but modal auxiliary verbs do not carry tense. The tense of the sentence will come from the rest of the verb phrase.
May is generally used to express possibility or permission, or to ask for permission.
1. I may try out for the school play.
2. When you are finished with the test, you may read a book quietly while you wait.
3. May I use the restroom, please?
Might is also used to express possibility or permission. Some sources say that might expresses a more remote possibility than may-there are conditions that would have to be met for the action to occur. In addition, might can be used to ask for permission, but it signifies a more polite and formal request than may.
1. I might choose Susan B. Anthony for my research topic, but only if Indira Gandhi is already taken.
2. Might I bring you a cup of tea?
In most instances, may and might can be used interchangeably. There are a few special instances when might is preferable.
1. When talking about something that might have happened in the past, but didn't actually happen.
a. Maurice survived the bike wreck, but he might have been hurt badly if it weren't for his helmet.
2. If you are reporting something that another has said may happen, then you would use might.
a. She said it might rain today.
3. You can use might to show annoyance.
a. You might have let me know that you would not be home for dinner!
Here is an instance where may is preferable-to express a wish or hope for another.
1. May your dreams come true.
In summary, in most of our everyday speech, may and might can be used interchangeably to express possibility. In a few instances, one is preferable to the other.
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