We use the Third Conditional to talk about impossible conditions, impossible because they are in the past and we cannot change what has happened. We often use this language to talk about regrets.
condition | result | |
Past Perfect | WOULD HAVE + Past Participle | |
If | I had won the lottery | I would have bought a car. |
Notice that we are thinking about an impossible past condition. You did not win the lottery. So the condition was not true, and that particular condition can never be true because it is finished. We use the past perfect tense to talk about the impossible past condition. We use WOULD HAVE + past participle to talk about the impossible past result. The important thing about the third conditional is that both the condition and result are impossible now.
Look at some more examples in the tables below:
IF | condition | result |
past perfect | WOULD HAVE + past participle | |
If | I had seen Mary | I would have told her. |
If | Tara had been free yesterday | I would have invited her. |
If | they had not passed their exam | their teacher would have been sad. |
If | it had rained yesterday | would you have stayed at home? |
If | it had rained yesterday | what would you have done? |
result | IF | condition |
WOULD HAVE + past participle | past perfect | |
I would have told Mary | if | I had seen her. |
I would have invited Tara | if | she had been free yesterday. |
Their teacher would have been sad | if | they had not passed their exam. |
Would you have stayed at home | if | it had rained yesterday? |
What would you have done | if | it had rained yesterday? |
Gracie Fields sings If I knew you were coming I'd have baked a cake, see if you can find more uses of the Third Conditional in this song...
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Lyrics:
SPOKEN: Come in! Well, well, well. Look who's here. I haven't seen you in many
a year.
If I knew you were comin' I'd've baked a cake, baked a cake, baked a cake
If I knew you were comin' I'd've baked a cake
Howdya do, howdya do, howdya do?
Had you dropped me a letter, I'd a-hired a band, grandest band in the land
Had you dropped me a letter, I'd a-hired a band
And spread the welcome mat for you
Oh, I don't know where you came from
'cause I don't know where you've been
But it really doesn't matter
Grab a chair and fill your platter
And dig, dig, dig right in
If I knew you were comin' I'd've baked a cake, hired a band, goodness sake!
If I knew you were comin' I'd've baked a cake
Howdya do, howdya do, howdya do?
If I knew you were comin' I'd've baked a cake, baked a cake, baked a cake
If I knew you were comin' I'd've baked a cake
Howdya do, howdya do, howdya do?
Had you dropped me a letter, I'd a-hired a band, grandest band in the land
Had you dropped me a letter, I'd a-hired a band
Spread the welcome mat for you
Oh, I don't know where you came from
'cause I don't know where you've been
But it really doesn't matter
Grab a chair and fill your platter
And dig, dig, dig right in
If I knew you were comin' I'd've baked a cake, hired a band, goodness sake!
If I knew you were comin' I'd've baked a cake
Howdya do, howdya do, howdya do?
Howdya do, howdya do, howdya do?
Howdya do-ooh-ooh-ooh-ooh-ooh