______ to reach them on the phone, we sent an email instead.
| A．Fail | B．Failed |
| C．To fail | D．Having failed |
However, at times this balance in nature is disturbed, ____ a number of possibly unforeseen effects.
| A．lying in | B．calling in | C．taking in | D．resulting in |
--- He has to finish the experiment today. He must be in the lab,____?
---That s quite possible.
| A．mustn't he | B．won't he | C．doesn't he | D．isn't he |
Let us suppose that you are in____ position of____ parent. Would you allow your child to do such a thing?
| A．a; a | B．a; the | C．the; a | D．the; the |
Our TV sets sell well, but ten years ago no one could have imagined such a big share in the market that they ____.
| A．were having | B．had had | C．were to have | D．had |
In salad bars the waiter does not bring you salad. You have to____ yourself, usually to as much as you want.
| A．bring | B．serve | C．help | D．supply |