钢材表面的除锈常用方法有（）
A.人工除锈
B.喷砂除锈
C.机械除锈
D.化学除锈
E.弹珠除锈
参考答案：A, B, C, D
在安装前将拆开的阀体、零件等用（）进行认真清洗。
A.水
B.专用清洗剂或煤油
C.汽油
D.洗涤液
The carrier is liable for loss of or damage to the goods or delay in delivery caused by fire，（）the claimant proves that the fire arose from fault or neglect on the part of the carrier，his servants or agents.
A.should
B.shall
C.that
D.if
