润滑油量多，压力高，有利于发动机的正常运转和润滑。
参考答案：错
Our government is trying its best to ____ the social security system to protect people's rights. [ ]
A. balance
B. reform
C. conduct
D. press
下列哪种物质是制造血红蛋白必需的
A．维生素B12 B．维生素K C．叶酸D．铁 E．内因子
