HE HAS WORKED AS A TEACHER SINCE 1999. A. HE DOES NOT WORK AS A TE...
31. He has worked as a teacher since 1999.
A. He does not work as a teacher from 1999 up to now.
B. He did not work as a teacher in 1999.
C. He worked as a teacher in 1999.
D. He began to work as a teacher in 1999.