Tom was about to close the window __________his attention was caught by a bird.
| A．when | B．if | C．before | D．since |
The cancer risks _______ with smoking have been well proved.
| A．combined | B．related |
| C．associated | D．caused |
_______ with his research work, the professor cared little about any other things.
| A．Occupying | B．Occupied |
| C．Having occupied | D．Being occupied himself |
_______ Bagrit’s predictions so remarkable is their accuracy.
| A．How many are | B．Why are |
| C．What makes | D．They make |
To British people，Canadians may sound American; to Americans，they may sound British. Canadians themselves insist on not being identified with .
A. either B. both C. any D: neither
We have a high regard for Mr. Black because he always tries to ________ his principles.
| A．live up to | B．look forward to |
| C．catch up with | D．put up with |