Past perfect simple
We use past perfect simple to say that some action happened before other action in the past.
It is also known as ‚earlier past‘ .
Had + past participle
I had left my old job before I started to look for a new one.
When I woke up I realised that I had had too much to drink the night before.
You had known him for 10 years when he died in a car crash.
He woke up to find out that he had left his wallet on a late night bus.
When she called home her dad told her that her mum had been taken to hospital with a concussion.
The film we saw last weekend was more enjoyable than we had previously imagined.
The show had been on stage for 3 years when they decided to change the actors.
had not + past participle
I hadn’t heard about her before she married that famous director.
I hadn’t had much teaching experience before I got this teaching job 2 years ago.
He hadn’t asked for her phone number until last week.
The sighting of that endangered species of bird hadn’t been confirmed until last weekend.
She hadn’t slept for two days when she decided to see her doctor about that.
Had I/you etc. + past participle
Had I known her before the accident last year?
Had you been to Italy before your business trip last month?
Had you known your wife for long before you got married?
Had he been a soldier before he started work in the gym?
Had she had any children when she met Tom?
Had they already had a car when they bought that new one?
We also use Past perfect simple with 3rd conditional.
We use 3rd conditional to talk about things which were possible in the past but not at present.
If + past perfect, would + present perfect
I had known about the homework, I would have done it by now.
If you had warned me about the boss’s bad mood, I wouldn’t have gone and told him about the glitch.
If we had known about his gambling problem, we would have tried to persuade him to get the professional help.
If the assassination attempt had not failed, the country would have descended into civil war.