Conditional Sentence

'IF' SENTENCES AND THE 'UNREAL' PAST

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:

'IF' CLAUSE	MAIN CLAUSE
If + simple present If you heat ice If it rains	simple present it melts. you get wet

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.
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

'IF' CLAUSE	MAIN CLAUSE
If + simple present If it rains If you don't hurry	Simple future you will get wet we will miss the train.

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.
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:

'IF' CLAUSE	MAIN CLAUSE
If + simple past If it rained If you went to bed earlier	Present conditional you would get wet you wouldn't be so tired.

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.
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:

'IF' CLAUSE	MAIN CLAUSE
If + past perfect If it had rained If you had worked harder	Perfect conditional you would have got wet you would have passed the exam.

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.
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:

'IF' CLAUSE	MAIN CLAUSE
If + past perfect If I had worked harder at school If we had looked at the map	Present conditional I would have a better job now. we wouldn't be lost.

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.