题干
The roots of a plant grow _________ the stem.
A：at the top of
B：in the bottom of
C：in the middle of
D：at the beginning of
答案(点此获取答案解析）
B
The roots of a plant grow _________ the stem.
A：at the top of
B：in the bottom of
C：in the middle of
D：at the beginning of
