Maxsus ta’lim vazirligi nizomiy nomidagi Toshkent davlat pedagogika universiteti qoshidagi akademik litsey Nurmatov J. N, Kudratov K. X

to separate adverbial clauses of time (often introduced by when, after, before, by the time (that), directly, during the time (that), immediately, the moment (that), now (that), once, since, until/till, whenever) and long phrases that come before or in the middle of the main clause

After he got married, Andy changed completely.

Now that it’s spring, her mood has improved enormously.

The book, once you’re done with it, can be returned to any branch of the library.

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  to separate from the rest of the sentence words or phrases that suggest if something is likely or suggest other possibilities (on the contrary, on the other hand), adverbs that act as conjunctions (however, consequently) and words or phrases that introduce examples (namely, for example)
  

On the other hand, we will soon run out of time.

Most of her friends, however, were rather keen on going swimming.

He could ask his brother to give them a lift, of course.

She took everything I had, namely, my watch and my wallet with all my money.

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