The two Chinese scientists have made a wonderful discovery, which marks a major _______ in the basic research in the field.
| A．reform | B．approach | C．boundary | D．breakthrough |
The 70-year-old man ______ exercises in the morning.
| A．takes | B．are taking | C．took | D．will take |
I don’t think that it’s true. She’s always ______ lies.
| A．tell | B．tells | C．telling | D．told |
How ______ you ______ with the new job?
| A．do, do | B．do, get along | C．are, doing | D．are, getting on |
--- Are these socks yours?
--- No. Mine ______ outside on the clothes line.
| A．are hanging | B．have hung | C．hang | D．hung |
I______ for Hong Kong on Saturday. Will you go to see me off at the airport？
| A．am leaving | B．am left | C．am going to leaving | D．left |