So sudden ________ that the enemy had no time to escape.
| A．did the attack | B．the attack did | C．was the attack | D．the attack was |
---- You shouldn’t have gone there alone last night.
---- But I ______, because Xiao Wang went there, too.
| A．didn’t | B．had to | C．did | D．should |
---- There is a lot of smoke coming out of the teaching-building there.
---- Really? It _____ be a fire, most probably.
| A．can | B．ought to | C．have to | D．must |
If you don’t wait _______ the red light, you will be punished by the policeman.
| A．at | B．under | C．for | D．on |
________ doesn’t seem to have been much difficulty in solving the problem.
| A．It | B．That | C．There | D．He |
It is fairly common in Africa for there______ a group of expert musicians surrounded by others who also join in the performances.
| A．being | B．to be |
| C．be | D．is |