Zahiriddin muhammad bobur nomidagi andijon davlat universiteti ingliz tili grammatikasi kafedrasi

Before expresses precedence:
Some months went by before they met again (Ganshina). I had written my letter before he came (Ganshina).
After expresses posteriority:
The heavies began again soon after it was light (Aldington). Bring me things after they are packed (Ganshina). Since expresses the starting point of the continued action or state: It has been reining ever since I came here (Ganshina). Since we came here, we hadn't a single sunny day (Ganshina). Till and until express the finishing point of an action or state: I'll be here till you come. Wait until I call.
As long as shows the limit of the continuation of the action in the principal clause:
You may keep the book as long as you like (Ganshina). You can stay here as long as you want (Hemingway). As soon as expresses a narrow temporal gap (interval) between the actions of the principal and subordinate clauses:
As soon as I saw Susan,I stopped noticing my surroundings (Bronte).
I'll phone you as soon as he comes.
Scarcely ... when, hardly ... when, no sooner ... than express immediate start of the the action of the subordinate clause after the action of the principal clause:
Hardly had I reached the station when the train started (Ganshina). Scarcely had I opened the door when a gust of windblow the can­dle (Ganshina).
No sooner had I reached home than a violent thunderstorm broke out (Ganshina).
The subordinate clause of time often modifies the whole principal clause, but there are rare cases when it modifies a part of the principal clause:

4. 
   I'll visit him when I go there.
   
5. 
   I want to visit him when 1 go there.
   

The English complex sentences with an adverbial clause of time the components of which are connected by the correlative subordinators scarcely ... when, hardly ... when, no sooner... than present a lot of difficulties for Uzbek students to acquire them.