Why does the Lake smell terrible?
-Because large quantities of water .
| A．have polluted | B．is being polluted | C．has been polluted | D．have been polluted |
These two kinds of ways are totally different in nature, and we should not _______ the two.
| A．confuse | B．embarrass | C．disappoint | D．discourage |
Wang Lin behaves well at table. This family tradition has been _____ for generations.
| A．taken down | B．turned around | C．passed down | D．picked up |
The government must be very ______ about setting a policy, making no decision until they are quite sure it is the right one.
| A．particular | B．concerned | C．cautious | D．certain |
The president said that it was a great honor for him ______ his country in the past two weeks.
| A．to visit | B．to be visiting | C．to have visited | D．to have been visited |
_____ into a top university, we students must show a strong ability in spoken and written English.
| A．Having been accepted | B．To be accepted |
| C．Being accepted | D．Accepted |