28.This pair of trouseis ____ too long for him.

A.is　　　　　　 B.be　　　　　　 C.are　　　　　 D.were

27.Your trousers____ dirty.You must have____ washed.

A.is;il　　　　　　 B.are;it　　　　　 C.are;them　　　　 D.is;them

26. The police ____ the murderer everywhere when he suddenly appeared in a theatre.

A. is searching for　　　　　　　　　　　 B. were searching for

C. are searching for　　　　　　　　　　 D. were searching

25."All____ present and all____ going on well," our monitor said.

A.is;is　　　　　　 B.are;are　　　　　 C.are;is　 　　　　　D.is;are

24.Many a man ____ come to help us.

A.have　　　　　　 B.has　　　　　　 C.is　　　　　　 D.are

23.Theis is one of the most interesting questions that ____ asked.

A.have　　　　　　 B.has　　　　　　 C. have been　　　 D.has been

22.He is the only one of die students who ____ elected.

A. are　　　　　　 B.have　　　　　 C.has　　　　　　 D.is

21.The United States of America　　　 one of the most developed countries in the world.

A.is　　　　　　 B.are　　　　　 C.was　　　　　 D.were

20. The Olympic Games ____ held every ____ years.

A.is;four　　　　　 B.are;four　　　　 C.is;five　　　　　 D.are;five

19. A chemical works____ built there.

A. is to being　　　　 B.have been　　　 C. were to　　　　　 D.has been