At first the experiment went on well, but ______ problems we hadn’t expected turned up later and it failed.
— Professor Smith, some students want to have a talk with you. ___ they wait here or outside?— Show them in now, please.
_______ , I lost heart in English learning, but my teacher often said to me, “Keep on working hard and you’ll succeed ”.
Success in life doesn’t happen_____. It’s the result of devoting yourself to what you’ve set out to do.
Our school has strict rules. Almost no one can ________ using cell-phones in class .
My boss hates interruptions, when he is trying to work.