Conditional ("if") sentences normally have two parts.
One part shows a result and the other shows a condition
on which the result depends. The condition is normally
preceded by if. In "He gets angry if he doesn't get what
he wants," the result is "he gets angry" and the condition
(introduced by "if") is "he doesn't get what he wants.

There are two main types of conditional sentences: real
and unreal. Real conditional sentences refer to situations
that are either true or possible. Unreal conditionals refer
to situations that are untrue, impossible or hypothetical;
conditional sentences of this type are often described as
being contrary to fact.

Let's look, first, at real conditionals.

There are two types of real conditional sentences. In the
first type, the result is known: it happens every time the
condition is met. In conditional sentences of this type,
when, whenever, or every time may be substituted for
if with no changein meaning:

If she studies, she gets good grades.

(When / Whenever / Every time she studies,
she gets good grades.)

 

If he's relaxed, he feels more confident.

(When / Whenever / Every time he's relaxed,
he feels more confident.)

 

If they have extra money, they put it
in their savings account.

(When / Whenever / Every time they
have extra money, they put it in their
savings account.)

Special Notes: