Here's some explanation of the conditionals we use in English. See how much you understand! It's also been added to Daniel's Reference Pages.
Conditionals in English
0 Conditional = something
which is generally true
If + simple present + simple present
e.g. If you heat butter, it melts.
1st Conditional =
possible
a) If + simple present + simple future
e.g. If you study hard, you will pass your exams.
b) Imperative +
or/and + simple future
e.g. Finish your job and you
will be happy.
c) Imperative +
if/in case + simple present
e.g. Call them if you need any help.
2nd Conditional =
imagining, improbable or impossible
If + simple past + simple conditional
e.g. If I were (was) rich, I would
buy a Ferrari.
If + past perfect + conditional perfect
e.g. If I had eaten chocolate, I would
have felt better.
Mixed Conditionals (2nd
+ 3rd ) = past & present
situations together
If + simple past + conditional perfect (2nd conditional for present + 3rd conditional for
past)
e.g. If tickets weren’t so expensive, I would have gone to the cinema last night.
If + past perfect + simple conditional (3rd conditional for past + 2nd conditional for
present)
e.g. If James hadn’t fallen off his bike, he would be champion now.