Some retired people have nothing to do. They often get together and ___for hours talking about their past experiences.
| A．look around | B．get around | C．turn around | D．sit around |
What ______ to so many students coming to the school gate?
| A．attracts | B．impresses | C．belongs | D．appeals |
Large quantities of water ______and lots of fish died.
| A．has been polluted | B．were polluted |
| C．is polluted | D．was polluted |
When was it ______ you met Yao Ming in the street?
| A．as | B．if | C．while | D．that |
How happy we _______, if you had come with us to the party.
| A．could be | B．may have been |
| C．would have been | D．were |
It is required that no smoking ______ in the school.
| A．was allowed | B．be allowed |
| C．would be allowed | D．had been allowed |