Use

The zero conditional is used to talk about results that are always true, such as scientific facts.

Example:

If I have an exam, I study a lot.

Explanation:

We use the zero conditional here because if you have an exam, you always study a lot. If I have is the ‘if’ clause, and I study is the main clause.

How to build

A sentence has an 'if' clause and a main clause. Clause can come first, but when the 'if' clause comes first, we use a comma. 'If' can also be replaced by 'when'.

If/when + simple present, simple present

• If it rains, I go by car.

• When it rains, I go by car.

simple present + if/when + simple present

• I go by car if it rains.

• I go by car when it rains.

More Examples

• If I drink too much, I feel sick.

• Water boils when it reaches 100 degrees Celsius.