42 Modals in the Past - May have/Might have

The verb May/Might belong to the group of modal auxiliary verbs. They are used to talk about the possibility for something to happen.

When a situation had the possibility to happen in the past, we use May and Might in the past structure.

For the Past forms of May and Might we have a sentence structure in this way:

In conditional sentences we only use past form of Might + have+ past participle, May + have + past participle is not used.

• He had a visa, he may have gone to Europe during holiday.
• They might have been busy yesterday, they were supposed to plant trees.
• This plant is quite dry, he might have forgotten to water it.
• I might have gone to Asia if there hadn’t been an earthquake. (NOT: I may have gone to Asia if there hadn’t been an earthquake.)

We use this structure to talk about possible events that could have happened in the past but we are not sure whether they happened or not.

We rarely use May and Might in the past, however if we do, we use it to talk about possible events that could have happened in the past but we are not sure whether they happened or not.

• For May, the structure is:
  May + have + past participle (e.g. She is still sick, she might have forgotten taking her medicine.);
• For Might, the structure is:
  Might + have + past participle (e.g. It is 21.30. They may have arrived an hour ago.)

For example:
— “She is still sick, she might have forgotten taking her medicine.” = We are not sure whether she took the pill or not.
— “It is 21.30. They may have arrived an hour ago.” = It is possible that they arrived, but we don’t know.
— “I might have bought a rabbit if my mom had let me.” - “I may have bought a rabbit if my mom had let me.” = May cannot refer to past situations in conditional sentences.

Let’s revise this content within the [Form] section. Take a look at the [Example] section that shows its use within a context.