---What do you think of the book? ---Oh,excellent. It's worth____a second time. A. to read B.to be read C, reading D,being read
Is this the school _______ you worked last year?
Is this school _____ you visited last year?
The Great wall is the only one of the buildings on the earth_____ seen from the moon.
Is there anything ________ I can do for you?
This is the first American film _______ I have ever seen.