课时作业(二十一) [必修5 Unit 1 Great scientists]
(限时：35分钟)
Ⅰ.单项填空
1．We all feel it is Jack as well as his wife that ________ for their son's bad performance at school.
A．are to blame B．is to be blamed
C．are to be blamed D．is to blame
2．The workers will go on strike if the demands they ________ are turned down.
A．put aside B．put through
C．put forward D．put away
3．[2012·辽宁卷] Rod loves ________ clocks. However, he never manages to put them together again.
A．taking apart B．giving away
C．making up D．turning off
4．Only after he had spent several nights working on the maths problem ________to wonder whether the problem was wrongly set.
A．he began B．that he began
C．he did begin D．did he begin
5．My brother is shy，so it is a great ________ for him to sing in front of the judges and audience.
A．honour B．benefit
C．characteristic D．challenge
