Third type if conditional

Type 3 conditional sentences, are truly hypothetical or unreal. In these sentences, the time is past, and the situation is contrary to reality. The facts they are based on are the opposite of what is expressed.

1. Form

In a Type 3 conditional sentence, the tense in the ‘if’ clause is the past perfect, and the tense in the main clause is the perfect conditional:

If it had rainedyou would have got wet

‘IF’ CLAUSE	MAIN CLAUSE
If + past perfect	Perfect conditional
If you had worked harder	you would have passed the exam.

Perfect conditional – form

The perfect conditional of any verb is composed of two elements: would + the perfect infinitive of the main verb (=have + past participle):

Subject	would	perfect infinitive
He They	would would	have gone… have stayed…
Affirmative
I	would	have believed …
Negative
She	wouldn’t	have given…
Interrogative
Would	you	have left…?
Interrogative negative
Wouldn’t	he	have been…?

Example: to go, Past conditional

Affirmative	Negative	Interrogative
I would have gone	I wouldn’t have gone	Would I have gone?
You would have gone	You wouldn’t have gone	Would you have gone?
He would have gone	She wouldn’t have gone	Would it have gone?
We would have gone	We wouldn’t have gone	Would we have gone?
You would have gone	You wouldn’t have gone	Would you have gone?
They would have gone	They wouldn’t have gone	Would they have gone?

In these sentences, the time is past, and the situation is contrary to reality. The facts they are based on are the opposite of what is expressed.

Type 3 conditional sentences, are truly hypothetical or unreal, because it is now too late for the condition or its result to exist. There is always an unspoken “but…” phrase:

If I had worked harder I would have passed the exam
(but I didn’t work hard, and I didn’t pass the exam).

If I’d known you were coming I’d have baked a cake
(but I didn’t know, and I haven’t baked a cake).

NOTE: Both would and had can be contracted to ‘d, which can be confusing. Remember that you NEVER use would in the IF-clause, so in the example above, “If I’d known” must be “If Ihad known“, and “I’d have baked” must be “I would have baked..”

Examples:

If I’d known you were in hospital, I would have visited you

I would have bought you a present if I’d known it was your birthday.

 If they’d had a better goalkeeper they wouldn’t have lost the game.

If you had told me you were on the Internet, I’d have sent you an e-mail.

Would you have bought an elephant if you’d known how much they eat? 

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