.The visitors did nothing but ______ tea and ______ to each other.
| A．drinking; talking | B．drink; talk |
| C．to drink; to talk | D．drank; talked |
. They were surprised that a child could work out the problem ______ they themselves couldn’t.
| A．once | B．while | C．then | D．if |
. --- I hear Jane has gone to the Holy Island for her holiday.
--- Oh, how nice! Do you know when she ______ ?
| A．was leaving | B．had left | C．has left | D．left |
. The factory was built in a secret place, around _____ were high mountains.
| A．where | B．it | C．that | D．which |
The teachers were discussing the research project that they would like to see _____ in the coming holiday.
| A．complete | B．completes | C．completing | D．to complete |
. --- It’s the office! So you ______ know smoking is not allowed here.
--- Oh, sorry.
| A．must | B．will | C．may | D．need |