Conditional sentences are made up of two parts: the if clause, or the condition, and the main clause, where we see the result if the condition is completed.
Type 0 Conditional
Use this for facts, things that are always true:
If you pay attention, you learn.
If you learn, you get better results in your exams.
If you get better results in your exams, your parents are happier.
We use the present simple in the if clause and the present simple in the main clause too.
When can also be used in a similar way to if:
When it rains, we stay inside the house.
Type 1 Conditional
Use this for situations which are in the future and are hypothetical, but which could easily happen – there is a strong probability of the situation occurring.
If you eat too much, you will get fat.
If you get fat, you will have to buy new clothes.
If you have to buy new clothes, you will be poor.
Here we use the present simple in the if clause and the future (typically will + infinitive).
When can also be used in a similar way to if:
When the summer comes, we’ll go to the Antarctic on holiday.
Type 2 Conditional
Use this for situations which are in the future and are hypothetical, but which probably will not happen – the probability of the situation is occurring is low.
If Valencia CF had a lot of money, Émery would buy good players.
If Emery bought good players, Valencia CF would win a lot matches.
If Valencia CF won a lot of matches, Valencia CF would win the league.
We use the past simple in the if clause and the conditional, would + infinitive, in the main clause.
When is not used for this type of conditional sentence.
Type 3 Conditional
Use this for situations which are in the past and where you want to talk about how the situation would be different if something else had happened.
If Spain had lost against Holland, Hollan would have won the World Cup.
If Holland had won the World Cup, Iker Casillas would not have been happy.
If Casillas had not been happy, he would not have kissed Sara Carbonero.
When is not used for this type of conditional sentence.
