41- --We will do what we can ____ourselves this term。

　　---It’s high time for you to work hard。

　　A.improve B.to improve C.be improved D.be improving

　　42---What happened to Tom?

　　---He was crossing the street ____ a motorbike hit him from behind。

　　A.while B.when C.until D.because

　　43---Dad，what’s the sea like?

　　---Well，it’s large and full of water。 It covers about _____ of the earth。

　　A.one third B.three quarter C.three-fourth D.three quarters

　　44。 ---May I go out for an outing with you tomorrow?

　　---If your mother______。

　　A。 will let B。 will allow C.let D.agrees

　　45---Would you like ______ some fruit?

　　---No thanks。 I don’t feel like _____ anything now。

　　A.to have，to eat B.having， to eat C。 to have ， eating D。 having ，eating

　　46---There can be no life on the earth without water。

　　---That’s right.Water _____ everywhere。

　　A.needs B.is needing C.is needed D.needed

　　47---Were you late ____the meeting?

　　---No，I arrived there ten minutes______ the meeting started。

　　A.for， before B。 at， before C。 for ，till D。 at ，after

　　48---Excuse me，______ I don’t think you can smoke here。

　　----Sorry I didn’t know this is none-smoking zone。

　　A。 and B.but C.so D.then

　　49---How many English words had you learned _____ the end of last term?

　　----Aound 2000，but I’ve forgotten most of them。

　　A.by B.at C.to D.on

　　50。---Are you learning art now during your spare time?

　　----No。 I’ve stopped _____ Chinese medicine instead。

　　A.to learn B.learning C.dropping D.to give up