Conditional 0 and 1

​if clause and main clause

• All conditional sentences have two parts: the if clause and the main clause. It doesn’t matter which clause comes first, but when the if clause comes first, we should put a comma after it.

  • If it rains, we’ll stay home

  • We’ll stay home if it rains.

   

​Zero Conditionals – If clauses

Zero conditionals are used for facts that are generally true and do not change. It refers to a general situation that always happens (for example in the rules of a game) if a condition is met. The condition always has the same result.

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The zero conditional uses the present simple in the if-clause and in the main clause.

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Zero Conditionals are also known as Type 0 conditionals (general truth – general rule)

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​The first conditional is used to talk about things that might happen in the future if a condition is present. We don’t know if those things will happen or not, but they are a real possibility.

• If you study, you‘ll pass. 

• If you help me, I’ll have finished by the end of the month.

We don’t use will in the if clause.

• I’ll help you if you need me (NOT if you will need me)

unless = if (not)

  We can also use unless in conditional sentences to mean if … (not)

• I won’t go on holiday unless I save some money.

• = I won’t go on holiday if I don’t save some money.

• In the first conditional, the verb in the if clause is present and the verb in the main clause is future (will).

• If you don’t go to sleep, you’ll be very tired tomorrow.

• Theif clause may have a present or a future meaning, but the verb is always in present (NOT future)

• If you are a good boy tomorrow, mummy will buy you a present. (NOT If you will be a good boy)

• ​​Main clause: will, modal verb, imperative

In the main clause, we can use may, might, can, must, should instead of will.

• If he doesn’t train harder, he may/might lose the championship.

• If your room is tidy, you can leave.

• If you want to lose weight, you must/should eat less sugary things.

Or we can also use an imperative instead of will.

• If you arrive after midnight, ring me on my mobile

​When we are talking about the future we use the present, (NOT will) after the expressions when, as soon as, until, once, before, after, while. After these expressions we can use any form of present (present simple, present continuous, present perfect) to talk about the future.

• I’ll go to bed as soon as I finish my homework. 

• When I am 65, I will retire. 

• I won’t leave until you arrive. 

As it happens with the conditional sentences, we use a comma when we begin the sentence with a time clause. But we don’t use a comma if we put the time clause at the end of the sentence.

• When I am 65, I will retire. 

• I will retire when I am 65. 

Use a modal verb where possible

will

can

may

might​