In this section you will find information on sentences containing the word 'if', the use of conditional tenses, and the 'unreal past', that is, when we use a past tense but we are not actually referring to past time.
If and the Conditional
There are four main types of 'if' sentences in English:
1. The 'zero' conditional, where the tense in both parts of the sentence is the simple present:
In these sentences, the time is now or always and the situation is real and possible. They are often used to refer to general truths.
| IF' CLAUSE | MAIN CLAUSE |
|
If + simple present |
simple present |
2. The Type 1 conditional, where the tense in the 'if clause is the simple present, and the tense in the main clause is the simple future
In these sentences, the time is the present or future and the situation is real. They refer to a possible condition and its probable result.
| IF' CLAUSE | MAIN CLAUSE |
|
If + simple present |
Simple future |
3. The Type 2 conditional, where the tense in the 'if' clause is the simple past, and the tense in the main clause is the present conditional:
In these sentences, the time is now or any time, and the situation is unreal. They are not based on fact, and they refer to an unlikely or hypothetical condition and its probable result.
| IF' CLAUSE | MAIN CLAUSE |
|
If + simple past |
Present conditional |
4. The Type 3 conditional, where the tense in the 'if' clause is the past perfect, and the tense in the main clause is the perfect conditional:
In these sentences, the time is past, and the situation is contrary to reality. The facts they are based on are the opposite of what is expressed, and they refer to an unreal past condition and its probable past result.
| IF' CLAUSE | MAIN CLAUSE |
|
If + past perfect |
Perfect conditional |
5. A further type of 'if' sentence exists, where Type 2 and Type 3 are mixed. The tense in the 'if' clause is the past perfect, and the tense in the main clause is the present conditional:
In these sentences, the time is past in the 'if' clause, and present in the main clause. They refer to an unreal past condition and its probable result in the present.
| IF' CLAUSE | MAIN CLAUSE |
|
If + past perfect |
Present conditional |