Modal verbs (our enemy)

Modal verbs

Could/Could have

We use could to say that somebody had the general ability or permission to do.

 (ex) He could speak five languages. If you want to say somebody did something in a specific situation, use was/were able to or managed to.

We use could for actions that are not realistic.

(ex) I’m so tired, I could sleep for a week. <= as you can see, it is impossible to do that I sleep for a week. That’s why I put “could”. And, we use could to say that something is possible now or in the future. The meaning is similar to might or may.

If we say about past, you will use “could have”. (ex) I was so tired, I could have slept for a week.

May/Might

We use may or might to say that something is possible. And, for the past we use may have or might have. (ex) She may have been asleep. / You might have left it at work.

Could is similar to may or might but couldn’t is different from may not or might not.

Should

We can use should when something is not right or what you expect. (ex) She should be here by now (she isn’t here yet, and this is not normal)

We also use should to say that we expect something to happen. (ex) Akari has been studying hard for the exam, so she should pass. (= I expect her to pass)