采用油脂润滑的滚动轴承,加油时应加满轴承室容积的()即可。
A.全部
B.1/2
C.1/3~1/2
D.1/4
参考答案:C
What will the man do [A] Go away. [B] Drive a car. [C] Help the woman.
中国植物群落分类的原则是______原则。