Although the causes of cancer_____, we do not yet have any practical way to prevent it.
A.are being uncovered | B.have been uncovering | C.are uncovering | D.have uncovered |
We had planned to arrive at the park at 9 a.m., but unluckily, the car __ on the way.
A.broke away | B.broke down | C.broke up | D.broke into |
Even when I am able to get in touch with the manager and tell him your request, I cannot __ he will reply.
A.stress | B.appeal | C.inform | D.guarantee |
__ will be good for you to spend one hour exercising outdoors every day.
A.That | B.This | C.It | D.One |
If you are inposition of __ teacher, will you allow your students to play computer games all day long?
A./; a | B.a; / | C.the; / | D.the; a |
Once __________sport has become less popular, it has to make __________way for new sport which are more popular to enter into the Olympics.
A.the;a | B.a;/ | C./;the | D.the;/ |