Look at the sign, Sir. We don’t permit ________ in the hall.
| A．smoke | B．to smoke |
| C．smoking | D．to have a smoke |
The monument was built in honor of the explorer who was believed＿＿the big river.
| A．to have discovered | B．to have been discovered |
| C．to be discovered | D．having been discovered |
Jennifer is always absent from school，＿＿I suppose is why she is blamed now and then.
| A．which | B．who | C．that | D．what |
-Jenny took the 8：00 bus to Guangzhou this morning.
-Really? He＿＿the 9:00 train. It's much more comfortable and safer to travel by train.
| A．could have taken | B．should take |
| C．must have taken | D．can take |
Junk messaging has been a headache for years, ＿＿the action taken by the authori-ties has not yet produced the results expected
| A．as | B．but | C．so | D．before |
Most museums are just for looking. But today some of them have things for you to touch.The ＿＿say,“＿＿”
| A．signs; Do touch | B．notices; To touch |
| C．signals; Be touching | D．signs; No touching |