问题
选择题
—Shall we go out for a walk?
—Sorry, I can't. I _____ my homework.[ ]
A. do
B. did
C. am doing
D. was doing
答案
答案:C
—Shall we go out for a walk?
—Sorry, I can't. I _____ my homework.[ ]
A. do
B. did
C. am doing
D. was doing
答案:C