Conditional Sentence

موضوع: Conditional Sentence الأربعاء يونيو 30, 2010 11:43 am

Conditional Sentence

• Conditional sentences have two parts:
a. The if-clause
b. The main clause
e.g. If she comes, I'll visit her.
the if-clause the main clause

• The verb in the if-clause is in simple present tense and the verb in main clause is in simple future (if + s + v(s), s + will/shall + base); e.g.
If she studies hard, she will pass the exam.
This type shows that the verb in if-clause is quite probable.

• Notes:
- (may and might) can be used instead of will and shall in the main clause to show possibility, as in the following structure:
If + s + v(s), s + may/might + base
If she studies hard, she may pass the exam.
- (may and can) are used instead of will and shall to show permission and ability respectively; e.g.
If you feel tired, you can go home.
- (must and should) are used in the main clause to show obligation or advice; e.g.
If you have an exam, you should study.
- Sometimes simple present is used in the main clause to show facts, as in this structure: if + simple present, s + simple present; e.g.
If you heat the ice, it turns to water.
- Present continuous is used instead of simple present to show present actions or future arrangement
If + present continuous, s + will/shall + base
If you're looking for your son, you will find him in the garden.
- The present perfect can be used in the if-clause:
If + present perfect, s + will/shall + base
If he has written a letter, I'll post it.

• Conditional part 2 (are not expected never to happen):
The verb in if-clause is in the past tense and the verb in main clause consists of 'would':
If + simple past, s + would + base
If I had a book, I would lend it to you.
This type of sentences indicates unreality.
• Note: the if-clause is in the past tense, but isn't a real past. This tense is only use to show unreality.

• The uses of conditional part 2:
- When the situation is in contrast with the facts; e.g.
If I were you, I would buy a new car.
- When we don't expect the action in the if-clause to happen; e.g.
If I dyed my hair blue, everyone would laugh at me.

• Note: (might and could) can be used instead of would to show: ability, certainty, and possibility; e.g.
If you studied hard, you could succeed.
If I had time, I might meet her.
If you finished, you could leave.

• Conditional part 3:
The verb in if-clause is in the past perfect while the verb in the main clause consist of (would + have + p.p.)
If + s + had + p.p., would + have + p.p.
If I had known you are coming, I would have waited for you.

• Note:
- The action in the if-clause can't be fulfilled (not complete).
- (could, might) can be used instead of would to show: ability, possibility, and permission); e.g.
If you had done your job, you could have gone home.