. The plan ___ just because people were unwilling to co-operate（合作）。
| A．broke down | B．pulled down | C．turned down | D．put down |
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 |
—I’m sorry．That wasn’t of much help．
— Oh, _______ . As a matter of fact，it was most helpful．
| A．sure it was | B．it doesn’t matter | C．of course not | D．thanks anyway |
From time to time a crocodile has snatched someone _______ he or she is even aware that the crocodile is there.
| A．when | B．until | C．since | D．before |
_____ 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 |