Conditionals

There are four main kinds of conditionals:

Conditional type zero:

Form:

(if + present simple, ... present simple)

Usage:

General truths

Example:If you heat water to 100 degrees, it boils.

Conditional type one:
Form:

(if + present simple, ... will + infinitive)

Usage:

A possible condition and its probable result

Example:
If it rains tomorrow, we'll go to the cinema.

Conditional type two:
Form:

(if + past simple, ... would + infinitive)

Usage:

A hypothetical condition and its probable result

Example:
If I had a lot of money, I would travel around the world.

Conditional type three:
Form:

(if + past perfect, ... would + have + past participle)

Usage:

An unreal past condition and its probable result in the past

Example:
If I had gone to bed early, I would have caught the train.