CONDITIONAL SENTENCES EXPLANATION

Conditional clauses begin with if. The conditional clause can come before or after the main clause. We have to use a comma at the end of the conditional clause when it comes first.

Examples: You'll fail if you don’t work harder.                

                    If you study, you’ll pass your exam.

We can use unless instead of If…not. It is very often used with first conditional:

Example:   Unless you study, you will fail your exam
FIRST CONDITIONAL

We use first conditional to talk about events which are possible.  It can refer to the future or the present.

Conditional clause     Main clause

If + present simple     future simple

If it rains,                  we’ll stay at home

If + present simple     modal verb

If you hurry,              you can be on time

If + present simple     imperative

SECOND CONDITIONAL

We use second conditional for unlikely situations in the present.

Conditional clause     Main clause

If + past simple            conditional                         

If I had money,            I would retire.

If + past simple            could

If I had money,            I could retire.

If + past simple            might

If I had money,            I might retire

THIRD CONDITIONAL

We use third conditional to talk about an event or situation which didn’t happen in the past.

Conditional clause     Main clause

If + past perfect          conditional + perfect

If I’d had an umbrella, I’d not have got wet

Instead of would, we can use could or might

I might have gone to the party if you had told

 Other words with conditional meaning

Many words and expressions can be used with a meaning similar to if and with similar verb forms.

Some of the commonest are provided, providing, supposing, as long as, on condition that.