4#油主要用于水泵和其他低转速的、高负荷的轴承和轴颈润滑。
参考答案:对
----Did you get what the teacher said?
----No. So softly _____ that I could hardly hear her.
A.spoke she
B.she spoke
C.did she speak
D.she did speak
衬有绝缘层的钢铁制电缆导管