Past Modals

Should have, could have, and would have are sometimes called “modals of lost opportunity” because they describe situations when we are imagining that the past was different.

The general rule of Should, Could, and Would is:

• Should for recommendation / advice
  “If you want to lose weight, you should eat healthy food.”

• Could for possibilities
  “I have the day off tomorrow.”
  “Great! We could spend the day at the beach. Or we could go shopping.”

• Would for imagining results
  “If I were rich, I would buy a boat.”

Click here to review the difference between should, could, and would.

The same general rule applies when using should have, could have, and would have for imaginary past situations.

Should Have

Use should have to say that a different action was recommended in the past.

If you arrive late to English class, you can say:

“I should have left my house earlier.”

If you regret an argument, you can say:

“I shouldn’t have yelled at you yesterday. I’m sorry.”

You can also use should have / shouldn’t have to tell other people that a different action in the past would have been better. If your son fails a test, you can say:

“You should have studied. You shouldn’t have played video games all weekend.”

Could Have

Use could have to talk about possibilities if something had been different in the past.

For example, someone who didn’t go to college can say: