The boy burst into tears ________ he saw his mother.

___ you lose the paper document, sign in www. Sina.com, __ you might download all you need.  

I have heard a lot of good things about you         I came back from abroad.

“Ungelivable” is so new an English word coined on the Internet ______ is forbidden to appear in official media or documents at present.

  --It is a long time ______ I saw you last year.
--Yes. And it will be some time ______ we see each other again.

Hi, Bob. How are you doing? It has been a long time _____ we left our junior middle school.

I recognized him _______ I saw him, though we had been apart for over a decade.

_______you’ve tried it, you can’t imagine how pleasant it is.

Work hard when young, ______ you will regret.

We’d better stay here a little longer    he turns up unexpectedly.