—Excuse me. Can I take this seat? — __ A girl sat here just now. Maybe she went to WC. A. I am afraid not B. I can’t hear you C. It doesn’t matter D. It’s nothing
My parents like the music ____ is quiet and gentle.
We often see Betty ____ the old man with his housework.
In our city, _____ middle school students want to work as a teacher in the future.
I found _____ necessary to save energy and protect the environment.
________ beautiful these postcards are! Where did you get them?