什么是辅助油泵？
参考答案：
调速油泵和润滑油泵称为辅助油泵。
—I often have hamburgers for lunch.
—It's bad for you ________ too much junk food. [ ]
A. eat
B. to eat
C. eating
D. ate
管道对接焊口的组对和坡口形式，应该要求对口的平直度1/100，全长不大于（）mm。
A、10
B、20
C、40
D、50
