You can’t imagine what great trouble they have _____ the problem _____.
| A．to solve; being talked about | B．solving; discussing |
| C．to solve; to talk about | D．solving; being discussed |
Jane has lost weight by going on __________ diet and taking __________ exercise every day.
| A．a；an | B．a；/ | C．/；/ | D．/；an |
It was not until I came here ________ I realized this place was famous for not only its beauty but also its weather.
| A．who | B．that | C．where | D．before |
We observed some young men __________into the building at 11：00 last night.
| A．to slip | B．slipped |
| C．slipping | D．being slipped |
Hangzhou is __________beautiful city，and it is worth__________.
| A．a most；visiting | B．the most；to visit |
| C．a most；to visit | D．the most；visiting |
The boy is old enough to __________the difference ________right and wrong.
| A．speak; from | B．tell; between |
| C．say; of | D．judge; from |