26．Don't forget _____ this book to John when you see him.

　 A. to return　　 B. returning 　C. return　　 D. to returning

25．-What's made Ruth so upset?

　 -_____ three tickets to the folk music concert.

　 A. Lost　　 B. Losing C. Because of losing D. Since she lost

24.Seeing is _

A.to believe　 B.believing　　　 C.believed　 D.being believed

23.______clean is a safeguard against disease.

　A.To be keeping　 B.Kept　　　 C.Keep　　　 D.Keeping

22.What about _________ to the concert with us ?

　 A.we go　　 B.we going　　 C.going　　　 D.to go

20.The story was so funny that we ___________.

A.couldn't help laugh　　　　　't but laugh

C.couldn't help laughing　　　　 D.couldn't help but to laugh

19.His parents insist on ____________ to college.

　A.he should go　 B.he go　　　　　 C.his going　　　 D.him to go

18.Keep on ______ and you will succeed.

　 A. a try　　 B. try　　 C .triing　　　 D .trying

17.We should often 　practise ____ English with each other.

　 A. to speak　　　 B. spoke　　　 C. speak　　 D. speaking

16. My brother keeps _________ me with my work.

　　 A. to help　　 B. help　　　 C. helping　　　 D. helped