David and Jack, _____so much alike each other, were often considered _____ twin brothers.
| A．looking; to be | B．looking; being | C．looked; to be | D．being looked; being |
— Did you call on any of your old friends when you returned to your hometown ?
—______ of them . They were all very busy .
| A．Nobody | B．None | C．Both | D．Neither |
It took seven years __________ they finally got married.
| A．since | B．after | C．before | D．when |
The students asked me ____________ going to be held.
| A．when is the meeting | B．when the meeting was |
| C．if was the meeting | D．if the meeting is |
In the past month, cruel snowstorms hit some European countries and America ,great transportation problems in these countries.
| A．causing | B．caused | C．to cause | D．having caused |
______he has made up his mind, no one can make him change it.
| A．Although | B．Unless | C．Until | D．Once |