In order to continue to learn by ourselves when we have left school, we must ______ learn how to study in the school now.
| A．in all | B．after all |
| C．above all | D．at all |
He is disappointed. He appears ____ what has happened to his competition.
| A．knowing | B．to know |
| C．having known | D．to have known |
I was watching the news on TV ________ the power went off.
| A．when | B．as | C．while | D．until |
It was not until I failed in the test ______ I realized I had wasted too much time instead of preparing for it fully.
| A．did | B．before | C．that | D．where |
As is widely acknowledged, a great number of traffic accidents ____ numerous deaths and countless property loss all over the world very year.
| A．subscriber to | B．contribute to |
| C．result from | D．aim at |
Mr. Lee suggested that all of us go out to have a walk to refresh our mind ________ classes.
| A．among | B．during | C．without | D．Between |