采煤机上必须装有能停止或开动滚筒以及能停止工作面刮板机的闭锁装置.（）
参考答案：对
---Look! The telephone is broken. Someone damaged it ________ purpose.
---That may be right. But perhaps it was broken _________ accident.
A．on; by
B．by; by
C．on; on
D．by; on
血沉增快见于以下疾病，但除了（）。
A.多发性骨髓瘤
B.巨球蛋白血症
C.系统性红斑狼疮（SLE.
D.真性红细胞增多症
E.严重贫血
