. Some of the suspects(嫌疑犯) ________ refused to answer and kept their mouths shut.
| A．questioning | B．being questioned |
| C．questioned | D．to be questioned |
I visited Mr. Johnson during his stay in Shanghai he attended a most important conference there.
| A．when | B．which | C．where | D．in which |
The time is drawing near food raised in space will directly benefit human below.
| A．where | B．when | C．whether | D．why |
Electrical products no longer in use contain dangerous materials which can be released into the environment when they are _____.
| A．taken apart | B．given away | C．fixed up | D．handed over |
There can be little doubt _____ bombing Libya would drive thousands more to take up arms.
| A．why | B．Whether | C．that | D．How |
The train was crowded and I had to get into a carriage _______ there were already seven other passengers.
| A．which | B．where | C．what | D．when |