—Hi, Nancy, I         you had come back. So have you graduated from college?

  —Yes. I_______ French for four years in Nanjing.

A. don’t know,have studied          B.didn’t know, had studied 

C. didn’t know,studied              D.don’t know, am studying

—Hi, Nancy, I         you had come back. So have you graduated from college?
—Yes. I_______ French for four years in Nanjing.

-----Hi, Nancy, I didn’t know you had come back. So have you graduated from college?

---- Yes. I _____ French for 5 years in Nanjing.

A. have studied     B. studied    C. had studied   D. am studying

-----Hi, Nancy, I didn’t know you had come back. So have you graduated from college?

---- Yes. I _____ French for 5 years in Nanjing.

---Hi, Nancy, I didn’t know you had come back. So have you graduated from college?

--- Yes. I ______ French for 5 years in Nanjing.

1. A.
   have studied
2. B.
   studied
3. C.
   had studied
4. D.
   am studying