FORM

[If ... Past Perfect ..., ... would have + past participle ... ]

[... would have + past participle ... if ... Past Perfect ...]

USE

The Third Conditional is used to talk about imaginary situations in the past. You can describe what you would have done differently or how something could have happened differently if circumstances had been different.

Examples:

* If I had owned a car, I would have driven to work. But I didn’t own one, so I took the bus.
* She would have traveled around the world if she had had more money. But she didn’t have much money, so she never traveled.
* I would have read more as a child if I hadn’t watched so much TV. Unfortunately, I did watch a lot of TV, so I never read for entertainment.
* Mary would have gotten the job and moved to Japan if she had studied Japanese in school instead of French.
* If Jack had worked harder, he would have earned more money. Unfortunately, he was lazy and he didn’t earn much.
* A: What would you have done if you had won the lottery last week?
B: I would have bought a house.
* A: What city would you have chosen if you had decided to move to the United States?
B: I would have chosen Seattle.

IMPORTANT Only use “If”

Only the word “if” is used with the Third Conditional because you are discussing imaginary situations. “When” cannot be used.

Examples:

* I would have bought that computer when it had been cheaper. Not Correct
* I would have bought that computer if it had been cheaper. Correct

EXCEPTION Conditional with Modal Verbs

There are some special conditional forms for modal verbs in English:

would have + can = could have

would have + shall = should have

would have + may = might have

The words “can,” “shall” and “may” cannot be used with “would have.” Instead, they must be used in these special forms.

Examples:

* If I had gone to Egypt, I could have learned Arabic.
* If she had had time, she might have gone to the party.

The words “could,” should,” “might” and “ought to” include Conditional, so you cannot combine them with “would have.”

Examples:

* If I had had more time, I could have exercised after work.
* If he had invited you, you might have gone.