Conditional

Conditional tenses are used to speculate about what could happen, what might have happened, and what we wish would happen. In English, most sentences using the conditional contain the word if. Many conditional forms in English are used in sentences that include verbs in one of the past tenses. This usage is referred to as "the unreal past" because we use a past tense but we are not actually referring to something that happened in the past. There are five main ways of constructing conditional sentences in English. In all cases, these sentences are made up of an if clause and a main clause. In many negative conditional sentences, there is an equivalent sentence construction using "unless" instead of "if".

Conditional sentence type Usage If clause verb tense Main clause verb tense
Zero General truths Simple present Simple present
Type 1 A possible condition and its probable result Simple present Simple future
Type 2 A hypothetical condition and its probable result Simple past Present conditional or Present continuous conditional
Type 3 An unreal past condition and its probable result in the past Past perfect Perfect conditional
Mixed type An unreal past condition and its probable result in the present Past perfect Present contditional

The zero conditional

The zero conditional is used for when the time being referred to is now or always and the situation is real and possible. The zero conditional is often used to refer to general truths. The tense in both parts of the sentence is the simple present. In zero conditional sentences, the word "if" can usually be replaced by the word "when" without changing the meaning.

If clause Main clause
If + simple present simple present
If this thing happens that thing happens.
If you heat ice it melts.
If it rains the grass gets wet.

Read more about how to use the zero conditional.

Type 1 conditional

The type 1 conditional is used to refer to the present or future where the situation is real. The type 1 conditional refers to a possible condition and its probable result. In these sentences the if clause is in the simple present, and the main clause is in the simple future.

If clause Main clause
If + simple present simple future
If this thing happens that thing will happen.
If you don't hurry you will miss the train.
If it rains today you will get wet.

Read more about how to use the type 1 conditional.

Type 2 conditional

The type 2 conditional is used to refer to a time that is now or any time, and a situation that is unreal. These sentences are not based on fact. The type 2 conditional is used to refer to a hypothetical condition and its probable result. In type 2 conditional sentences, the if clause uses the simple past, and the main clause uses the present conditional.

If clause Main clause
If + simple past present conditional or present continuous conditional
If this thing happened that thing would happen. (but I'm not sure this thing will happen) OR
that thing would be happening.
If you went to bed earlier you would not be so tired.
If it rained you would get wet.
If I spoke Italian I would be working in Italy.

Read more about how to use the type 2 conditional with the present conditional and how to use the present continuous conditional in type 2 conditional sentence.

Type 3 conditional

The type 3 conditional is used to refer to a time that is