问题
选择题
When I came into the classroom, I saw Jack _____ something on the the blackboard. [ ]
A. is writing
B. was writing
C. to write
D. writing
答案
答案:D
When I came into the classroom, I saw Jack _____ something on the the blackboard. [ ]
A. is writing
B. was writing
C. to write
D. writing
答案:D