Our teacher demanded that all of us ______ English every day.
| A．should practise to speak | B．would practise speaking |
| C．could practise speaking | D．practise speaking |
He spent much of the evening with Robert Green, _________he had hardly seen in the thirty years since they had worked together at CBS.
| A．what | B．that | C．who |
D．whom |
At last, the boys found themselves in a pleasant park with trees providing shade and_________down to eat their picnic lunch.
| A．to sit | B．sat | C．sitting | D．having sat |
The researehers delermine what type of plants the virus can infect(感染) and_________insects can carry the virus.
| A．those | B．why | C．which | D．how |
—Did you get my letter?
—I received one just as I_________.
| A．set out | B．had set out | C．was setting out | D．would set out |
．When she called at his studio, she_________that he had gone to Japan.
| A．is told | B．was told | C．tells | D．told |