—Why wasn't John hired for the job?
—I don't know, but he ________.
| A．was | B．had been |
| C．should have | D．should have been |
The DiaoYu Island have been part of China’s territory since ancient times, __________as important fishing grounds of Taiwan.
| A．served | B．serving | C．to serve | D．having served |
Sun Yang, a young Chinese swimming talent, ___________several gold medals before 2012 London Olympics.
| A．won | B．has won | C．had won | D．were to win |
The government has taken some measures to solve the shortage of electricity, but it may be some time ____________ the situation improves.
| A．since | B．when | C．unless | D．before |
Mary had to go to a meeting，so she left her children ___________ at home.
| A．playing | B．played | C．to play | D．having played |
A cell phone could ___________the energy which could activate your brain.
| A．give away | B．give off | C．give back | D．give up |