Could you tell me ________ late for the meeting yesterday?
A:why were you
B:why you were
C:why are you
D:why you are
—Shall we go hiking this weekend?—Sounds ____.
选项
A
B
C
D
实验
设计
目的
探究二氧化碳能与水反应
探究燃烧所需要的条件
探究铁生锈
需要氧气
探究空气中氧气的体积分数
我国横断山区“一山有四季,十里不同天”的主要成因是 ( )