There was a terrible traffic jam (= it was impossible for me to have arrived any earlier). He could have studied harder, but he was too lazy and that's why he failed the exam.Ĭouldn't have + past participle means that something wasn't possible in the past, even if you had wanted to do it.Julie could have bought the book, but she borrowed it from the library instead.They could have won the race, but they didn't try hard enough.I could have stayed up late, but I decided to go to bed early.Could have + past participleġ: Could have + past participle means that something was possible in the past, or you had the ability to do something in the past, but that you didn't do it.
These past modal verbs are all used hypothetically, to talk about things that didn't really happen in the past.
