The family is a cooperative enterprise for which it is difficult to _____ rules, because each family needs to work out its own ways to deal with its own problems.
| A．set up | B．put down | C．keep up | D．lay down |
_____ unemployment and crime are high, it can be assumed that the latter is due to the former.
| A．Before | B．Where | C．Unless | D．Until |
_____the Internet is of great help, I don’t think it’s a good idea to spend too much time on it.
| A．If | B．While | C．Because | D．As |
It was a matter of________ would take the position.
| A．who | B．whoever | C．whom | D．whomever |
In China, all the students work hard at school _________ going to university for higher education in the future.
| A．in the habit of | B．in the hope of | C．in search of | D．in honor of |
Robert is said ___________ abroad, but I don’t know what country he studied in .
| A．to have studied | B．to be studying | C．to study | D．to have been studying |