Mary _______ her mother with the housework, but she didn’t.
A．must have helped B．ought to have helped
C．must help D．should help
The local government announced that only when the fire was under control ________ to return to their homes.
A．the residents would be allowed B．had the residents been allowed
C．would the residents be allowed D．the residents had been allowed
He left home without saying a word, and _______ worries many people and is to be found out.
A．where he has gone B．where did he go
C．which place has he gone D．where has he gone
He came all the way to China for learning it better _______ for making money.
A．other than B．more than C．better than D．rather than
Evidence gained from observation and experiment is often used to _______ a scientific theory.
A．concern B．confirm C．consult D．combine
_______ be sent to work there?
A．Do you suggest who should B．Who do you suggest that should
C．Who do you suggest D．Do you suggest whom should
