He often helps the students _________he thinks are not quick at their studies.
| A．whom | B．whose | C．when | D．who |
We are satisfied with his job in our company. Everything goes better now than when he his work here.
| A．has started | B．would start | C．started | D．had started |
A clean environment can help the cityits economic development.
| A．achieve | B．permit | C．complete | D．promote |
—What made him so worried.
—his wallet.
| A．Having lost | B．Losing | C．Lose | D．Lost |
The job is great in terms of salary. It has its disadvantages,.
| A．though | B．however | C．even | D．therefore |
—Why are they taking all the equipment away？
—With the job , they are leaving.
| A．having done | B．being done | C．was done | D．done |