, ( I ) ( II ).
I
, , , , . .
If the weather is nice, we go for a walk. , .
If the weather was nice, we went for a walk. , .
If the weather is nice, we' ll go for a walk. , .
II
, , . should / would + Indefinite Infinitive to, - , Past Indefinite were to be.
If he were free, he would do it. , .
If we paid more attention to grammar, we should know the language better. , .
III
, , , . should / would + Perfect Infinitive, , Past Perfect.
I should not have been late yesterday, if my watch had been right. , .
.
if - ; in case - , ; suppose (that) - , ; on condition (that) - , ; provided (that) - , ; unless - ; but for - .
(THE SENTENCE)
- , .
The sun rises in the east. .
. - . - , , .
.
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