( )不是电梯检验报告的结论形式。
参考答案:整改后使用
冷箱一般是由()板翅式换热器串联或并联而成。
A.两台
B.三台
C.四台
D.多台
He was walking along the river ________ he saw a little dog struggling in the water. [ ]
A. while
B. when
C. as
D. which