Why are you so late today？
Three buses went by without stopping while I at the bus stop．（ ）
A．am waitingB．waited
C．have waitedD．was waiting
Xiandao Lake in Yangxin is the famous place ______ we'll visit next week．（ ）
A．thatB．whoC．whereD．whom
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