221、当输入杆在 5 毫米到 10 毫米之间时，测量活塞的伸长。

When the movement of input rod is ranged from 5 to10 mm, measure the piston retraction.

4 When the input lever is between 5 and 10 mm, measure the piston extension.

When the interval of input shaft changes between 5 and 10 mm, measure the expansion of the piston.

正确答案：B

1268、在燃油加放油的过程中,不允许进行氧气勤务。

1267、Manufacturers may omit systems not applicable to their product.

1266、在烤箱里烘干油滤

1265、Existing analyses were reviewed to identify components and areas that may have exhibited lower margins of safety.

1264、如果机轮温度上升到 257 度以上,易熔塞的芯就会熔化,轮胎就会漏气。

1263、确保工作区域有足够的空气流通。

1262、确保客舱压力外流活门打开。

1261、溶剂会对油漆造成损坏。

1260、Make sure that the generator operates smoothly.

1259、Approved adjectives are given in their basic form, with their comparative and superlative forms in parentheses、whereapplicable.