通过改变轴承盖与壳体端面间垫片厚度h来调整轴承的轴向游隙s的方法叫()法。
A.调整游隙
B.调整垫片
C.螺钉调整
D.调整螺钉
参考答案:B
In the picture you can see a boy swimming. His mother _____ him.[ ]
A. sees
B. is looking
C. is look at
D. is watching
尿路感染最常见感染途径是()。
A.上行感染
B.下行感染
C.淋巴道感染
D.直接感染
E.血行感染