在站内小车装卸（）时，应按轻型车辆提出申请。
A.两根水泥轨枕
B.八根木枕
C.长度12.5m的钢轨
D.其他材料500kg
参考答案：B, C
－David has made up his mind to continue with his studies.
－_______ and _______.
A．So he has; so have I
B．So has he; so have I
C．So he has; so I have
D．So has he; so I have
在太阳能利用中，太阳灶的受热面要做成黑色表面，而在室内供热用的辐射采暖板却不必做成黑色的，为什么？
