If I had known…: third and mixed conditionals

What you'll be able to do

Reflect on decisions and mistakes, explain what went wrong in a project, and imagine how your life would be now if something had been different.

Third conditional: an unreal past

if + past perfect, then would have + past participle: the situation didn't happen, and neither did the result.

• If I had known about the traffic, I would have left earlier.I didn't know, so I didn't leave earlier
• We wouldn't have missed the flight if the taxi had come on time.the taxi was late
• If she hadn't helped me, I would have failed the exam.she did help

Mixed conditional: a different past, a different present

if + past perfect, then would + base form (now).

• If I had taken that job in Sydney, I would be living in Australia now.past cause, present result
• If he hadn't moved abroad, he wouldn't speak three languages.his past explains his present

Other modals

Could have (it was possible) and might have (perhaps) replace would have:

• If we had booked earlier, we could have got cheaper seats.it would have been possible

Common mistakes

• If I would have known, I would have come. No would in the if-part: If I had known…
• If I had known, I would come. For a past result: I would have come.
• If I had took the job… Use the past participle: If I had taken…