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'll get angry if he doesn't get what
he wants," the result is "he'll get 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 take another look at real conditionals.

There are two types of real conditional sentences.

We saw that in the first, 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 change in meaning.

The second type of real conditional sentence is used for
situations that are possible. In this type of real conditional
sentence, the if clause is usually present tense and the
result clause is usually shown by will + a simple verb.
The result is possible, but it hasn't happened: it depends on
meeting the condition (shown by the if clause):

If she studies, she'll get good grades.

(Getting good grades is very likely for her,
but first she needs to study.)

 

If he's relaxed, he'll feel more confident.

(It's very likely that he'll feel more confident,
but first he needs to relax.)

 

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

(It's very likely that they'll put money in
their savings account, but it depends on
having something extra.)

 

If I see him, I'll give him your message.

(It's very likely that I'll give him your
message, but I can't do that if I don't see him.)

 

Special Notes: