More attention must be paid _________ the endangered animals..
| A．to protecting | B．protect | C．to protect | D．protecting |
Jim went to answer the phone. _____, Harry started to prepare lunch.
| A．However | B．Nevertheless | C．Besides | D．Meanwhile |
When ______questions in class，one should answer them as clearly as possible．
| A．asking | B．to ask | C．to be asked | D．asked |
After the bell rings，which indicates the ending of the exam，you_____stay where you are until all your papers are collected．
| A．shall | B．would | C．will | D．can |
—You were not listening；what troubled you?
—I my coming math exam．
| A．am thinking about | B．was thinking about | C．had thought about | D．will think about |
I am amazed at someone so rich _____ difficulty in paying what he owes you.
| A．as to have | B．who has no | C．that he has no | D．having |