I don’t believe these people have achieved success __________. They must have put much effort into their work.
| A．by coincidence | B．as usual | C．in particular | D．on purpose |
Shy people often avoid situationswould force them into close contact with other people．
| A．which | B．where | C．when | D．what |
—How long do you think it will be______man can finally solve the problem of cancer?
—Well，it depends
| A．when | B．until | C．after | D．before |
______ is known to us is that tobacco contains nicotine and other harmful products, so you should give up smoking.
| A．As | B．It | C．What | D．Which |
This book is considered to be the best novel of its kind ever.
| A．to write | B．writing | C．having written | D．written |
-- I can’t find my umbrella.
-- I saw George going away with____, but I’m not sure whether it is yours.
| A．it | B．that | C．one | D．the one |