We demanded that we __________ of any change in the plan.
A. informed
B. would be informed
C. be informed
D. had been informed
It’s necessary that he _________ a recognized qualification.
A. has
B. have
C. had
D. having
Much labour would have been saved if the electronic computers_________ before.
A. had invented
B. were invented
C. should have been invented
D. had been invented
Five minutes earlier, and we ____________ the last bus.
A. had caught
B. should have caught
C. could have caught
D. caught
微信支付 
支付宝支付