If you ________ go, at least wait until the storm is over.
| A．can |
| B．may |
| C．must |
| D．will |
We were told that we should follow the main road ___ we reached the central railway station.
| A．whenever | B．until | C．while | D．wherever |
Scientists say it may be five or six years ___ it is possible to test this medicine on human patients.
| A．since | B．after | C．before | D．when |
Tom’s and Joan’s ____ came to London last week.
| A．father-in-law | B．fathers-in-law | C．fathers-in-laws | D．father-in-laws |
You can hardly imagine the difficulty the woman had _____ her children.
| A．brought up | B．to bring up | C．bringing up | D．to have brought up |
No one ____ this building without the permission of the police.
| A．is leaving | B．is to leave | C．has left | D．will be leaving |