It took a long time for the effective use of natural gas_________．
| A．to be made | B．to make | C．being made | D．making |
—Have you been to the United States?
—Yes, only once. I ________ there only for seven days.
| A．have stayed | B．was staying |
| C．stayed | D．had stayed |
Would you please keep silent? The weather report ________ and I want to listen.
| A．is broadcast | B．is being broadcast |
| C．has been broadcast | D．had been broadcast |
The girl was very naughty. She hid her mother’s wallet without anyone ________ where it was.
| A．knows | B．knew | C．known | D．knowing |
We all believe that the project, if _______ according to plan, will definitely work out well.
| A．carrying out | B．being carried out |
| C．carried out | D．to be carried out |
After graduation, I’d like to find a job _______ I can use what I have learnt at school.
| A．whose | B．which | C．where | D．that |