I'm worried about our talent show tomorrow．
Be confident（自信的）！If you don't believe in yourself，_______ will．（ ）
A．nobodyB．anybodyC．everybodyD．somebody
Sorry，Miss Liu．I left my workbook at home．Must I hand it in today？
No，you ______．You ______ bring it here tomorrow．（ ）
A．mustn't； shouldB．can't；must
C．mustn't；mayD．needn't；can
The twins look exactly the same．______ of them are in my class．（ ）
A．EachB．BothC．EitherD．None
I don't think students should use mobile phones at school．
______．They really have a bad influence on our study．（ ）
A．I agree with youB．Not at all
C．No problemD．It's my pleasure
Many scientists believe that robots ______ able to talk like humans in 50years．（ ）
A．wereB．areC．will beD．have been
Why does the earth look blue in space？
Because most of the earth's surface ______ by water．（ ）
A．coversB．is covered
C．coverD．are covered