If it had been possible, I would have helped him, but I ______ too busy.

A. had been 　 B. would be 　 C. were 　 D. was

---Have you ever been to Shanghai?

---Yes. I ________ there a few months ago.

　 A have been　 B. went　 C. have gone

－What do you think of the four classics (名著)of China?

－I hear that they are wonderful, but I’ve read _______ of them.

　 A. all　　　　 B. both　　　　　　 C. neither　　　　　　 D. none

— Amy, I called you yesterday evening, but nobody answered the phone.

— Oh, I _________ a walk with my mother at that time.

A. take　　　　　　 B. took　　　　　　 C. am taking　　　　　 D. was taking