First Conditional

First Conditional: real possibility

A conditional is a sentence or part of a sentence that expresses a condition. It usually begins with the words "when," "if" and "unless."

A condition is what must happen before something else can happen.

We are talking about the future. We are thinking about a particular condition or situation in the future, and the result of this condition. There is a real possibility that this condition will happen. For example, it is morning. You are at home. You plan to play tennis this afternoon. But there are some clouds in the sky. Imagine that it rains. What will you do?

IF	condition	result
	present simple	WILL + base verb
If	it rains	I will stay at home.

We use the present simple tense to talk about the possible future condition. We use WILL + base verb to talk about the possible future result. The important thing about the first conditional is that there is a real possibility that the condition will happen. Here are some more examples (do you remember the two basic structures: [IF condition result] and [result IF condition]?):

IF	condition	result
	present simple	WILL + base verb
If	I see Mary	I will tell her.
If	Tara is free tomorrow	he will invite her.

·         In clauses with time words like when, after, until we often use the present tense forms to talk about the future:

1. I’ll come home when I finish work.
2. You must wait here until your father comes.

·          In conditional clauses with if or unless we often use the present tense forms to talk about the future:

1. We won’t be able to go out if it is raining.
2. If Barcelona win tomorrow they will be champions. 

·         We do not normally use will in clauses with if or with time words:

1. I’ll come home when I will finish work.
2. We won’t be able to go out if it will rain. rains.

·         but we can use will if it means a promise or offer:

1. I will be very happy if you will come to my party.
2. We should finish the job early if George will help us.

First Conditional