10.( 　　)He has been working _______ 16 hours today.

A.at 　B.for　 C.in　 D.from

9.(　　 )He’s been collecting shells _______ he was ten years old.

A.when　 B.while　 C.and　 D.since

8.(　　 )I’m interested _______ flying kites.

A.on　 B.in　 C.at　 D.for

7.(　　 )How long did you _______ yesterday?

A.skate　 B.skated　 C.skating　 D.to skate

6. If I _______ enough money, I _______ a hospital for SARS patients.

A.will have, build　 B.will have, will build

C.have, will build　 D.have, build

5.(　　 )How long have you been _______ sports?

A.watch　 B.to watch　 C.watching　 D.watched

4.(　　 )----- How long has the man been waiting?

------ He ____________ for 20 minutes.

A.has been waiting　 B.is waiting　 C.was waiting　 D.will wait