An interesting suggestion for measuring the atmosphere around Mars has been _________, thus leading a heated discussion among the scientists.
| A．come up | B．put forward | C．swept up | D．accused of |
Finally he reached a lonely island__ was completely cut off from the outside world.
| A．when | B．where | C．whom | D．which |
My father ____ for Beijing on business tonight.
| A．is about to leave | B．has been leaving |
| C．is leaving | D．would leave |
This is the first time that he your hometown.
| A．visited | B．visits |
| C．had visited | D．has visited |
The hero said he didn’t think twice ____ diving into the freezing river to rescue that child.
| A．before | B．after | C．until | D．when |
—Have you some new ideas?
—Yeah. I’ll tell you later.
| A．come about | B．come up |
| C．come out with | D．come up with |