It snowed heavily for three days and they were separated from the outside world.
| A．in the end | B．on end | C．by the end | D．at the end |
Scientists say it will be five or six years ________ it is possible to test this medicine on humans．
| A．after | B．before | C．since | D．When |
You are students in the No．168 Senior High School now, but you _______ in different junior high schools for three years．
| A．studies | B．have studied |
| C．studied | D．were studying |
I hope you can _______a solution to question as soon as possible．
| A．come up with | B．catch up with |
| C．put up with | D．end up with |
It is believed that a new kind of drug _____ by the scientists and they are hopeful that they will succeed in a few months．
| A．has been developed | B．is being developed |
| C．is developing | D．has developed |
The speaker raised his voice _____ make himself _____ by the listeners．
| A．so that; heard | B．in order to; hearing |
| C．so as to; heard | D．to; to be heard |