Sub + could have + V3 --------- (Past ability)
Sub + should have + V3 -------- (Regretted)
Sub + must have + V3----------- (feeling vexed)
Sub + might have + V3---------- (Past possibility)
e.g/
- I could have bought
a nice car like this last year.
- I could have
visited Japan last month if I wanted to.
- You could have sent
me the report on line.
- We should have
arranged everything in advance before we do anything.
- You shouldn’t have
driven carelessly.
- He should have
signed the contract.
- We must have seen
the manager and talked about that actually.
- You must have
brought the ID card, just then you will be allowed to get in.
- I actually must
have taken the money with me.
- A German company might
have built this bridge about 100 years ago.
- This bridge might
have been built by a German company about 100 years ago.
- They might have committed these crimes.
