My parents like the music ____ is quiet and gentle.
A. who B. that C. whose D. those
We often see Betty ____ the old man with his housework.
A. help B. to help C. helped D. helping
In our city, _____ middle school students want to work as a teacher in the future.
A. thousand B. thousand of
C. thousands of D. two thousands of
I found _____ necessary to save energy and protect the environment.
A. that B. this C. it D. one
________ beautiful these postcards are! Where did you get them?
A. What a B. How a C. How D. What
We can’t do well in examinations we study hard in school time.
A. if B. and C. since D. unless
