His lack of professional knowledge _______for the failure of the experiment.
| A．accounted | B．explained | C．counted | D．contributed |
If we work hard with a strong will, we _____ overcome any difficulty, however great it is．
| A．must | B．need | C．should | D．can |
—Did Betty go shopping with you yesterday?
—Even if she _____ a lot of studying, she would have preferred staying home to going shopping．
| A．didn’t have | B．shouldn’t have |
| C．hadn’t had | D．hasn’t had |
With masses of homework _____, I can hardly spare time to practice playing the piano．
| A．done | B．to do | C．doing | D．being done |
Take great pains to read _____ you can or you won’t have a better understanding of
life．
| A．as much as | B．books as much as |
| C．books as many as | D．as many books as |
We are sorry to have to announce that the Leeds train that _____ due to arrive at 12 ： 20 has been delayed by one hour and will now arrive at 13 : 20.
| A．was | B．is | C．will be | D．had been |