English conditional statements are grouped into four main types - zero, first, second, and third conditional.

Zero Conditional

Zero conditional is used for statements and facts which are perceived to be true.

Zero conditional has the form if + present simple + present simple. For example:
- If you need any help just call me.
- If you run fast you get tired.
All conditionals have two clauses, the if clause
- "If you have time, ..."
and the main clause
- "...come and visit us".

Either of these two clauses can come first:
- "If it rains take an umbrella" - or also:
- "Take an umbrella if it rains."

The zero conditional is often used with imperatives. For example:
- If you feel sick, see a doctor.
- If you can't take the heat, stay out of the kitchen.

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