问题:
【题文】 When the old man saw some litter on the ground, he quickly .
A.picked it up
B.picked up it
C.picked them up
D.picked up them.
【题文】 When the old man saw some litter on the ground, he quickly .
A.picked it up | B.picked up it | C.picked them up | D.picked up them. |
参考答案: