问题

John read an article ______ a competition.[ ]
A: in
B: on
C: at
D:of
B: on
C: at
D:of
正确答案是:
同类题型
Paul is _______ wilder than Tony.
The workers in the Huashan Mountains have to rubbish to keep the mountains clean.
_____haveyou practiced skating? —For five years.[ ]
I can’t stay up late. I have to go to bed__________11:00.[ ]
I like flowers. I hope to study at a school ____ many flowers and trees in it. [ ]