30.We don’t allow____here,but we can allow you ____in the next room.
| A．smoking,smoke | B．smoke,smoking | C．smoking,to smoke | D．smoke,to smoke |
This photo of mine was taken _______ stood the famous Eastern Bright Pearl in Shanghai.
| A．which |
| B．in which |
| C．where |
| D．there |
You should made it a rule to leave things _______ you can find them again.
| A．when | B．where |
| C．then | D．there |
In time of serious accidents, _______ we know some basic things about first aid,we can save lives.
| A．whether | B．until |
| C．if | D．unless |
The world is changing fast.I strongly believe that one will easily fall behind _______ he keeps on learning.
| A．unless | B．if |
| C．when | D．as |
The traffic is very_______.It’s quicker to walk there.
| A．noisy | B．crowded |
| C．narrow | D．heavy |