( C)7.--- How many people were there at the meeting?----_______.
A.Nobody B.No one C.None D.Nothing
(A )20.The doctor worked for ___ after twelve o’clock.
A.two more hours B.two another hour C.more two hours D.another two hour
( C)26.____John ____Jack may go with you because one of them must stay at home.
A.Neither； nor B.Both； and .C.Either； or .D.Not only； but also
括号中的是参考答案,请一个一个地详细说明
( C)7.--- How many people were there at the meeting?----_______.
A.Nobody B.No one C.None D.Nothing
为什么不选A，B