Question

Mary ______ as a volunteer teacher for 10 years.

1. A.
   works
2. B.
   will work
3. C.
   worked
4. D.
   has worked

Answer 1

D
根據(jù)時間狀語for 10 years十年了，說明本句為現(xiàn)在完成時態(tài)，所以選D。