Would have ( + the past participle of a verb)
is used when
referring to past unreal conditions (situations in the past
didn't actually happen, weren't true, or were hypothetical).
have is frequently
contracted to would've.
The negative form of would have is would
(which is very often contracted to wouldn't have).
If you had asked me, I would've helped you.
(I didn't help you because
you didn't ask me.)
If Julia had
had enough money, she would've
bought a car.
(Julia didn't buy a car because
she didn't have
If Fred hadn't
drunk so much coffee,
he wouldn't have been so nervous
(Fred was very nervous because
drunk a lot of coffee.)
If I hadn't
meant what I said, I wouldn't
(I said what I did because
that was exactly
what I meant to say.)
||In relaxed, casual speech, would've often
something like "WOODa." This
common in speaking, but would have or would've
be used in writing.
||In relaxed, casual speech, wouldn't have often
sounds something like "WOODena."
pronunciation is also common in speaking,
more conventional forms would not have or
wouldn't have should be used in writing.
the examples above, could
have and might
have are also possible, but if they are
the meanings are different.