在一般机械中用来传递运动和动力的链是（）。
A.牵引链
B.套筒滚子链
C.齿形链
D.起重链
参考答案：B, C
—Where did you have the discussion with Professor Snow?
—It was in the classroom ________ we had a biology lesson yesterday.
A．which
B．when
C．that
D．where
根据我国现行法律的规定，下列不属于合伙企业优点的是( )。
A．设立方便
B．收益大
C．税收优势明显
D．风险小
