为了保证导轨和运动部件相互配合良好,提高接触率,只要控制住导轨在水平面内和垂直内直线度误差即可。
参考答案:错
—I’m afraid a car is too expensive for me.
—But more and more Chinese can to buy one.
A.expect
B.afford
C.choose
D.offer
循环水系统正常运行中的检查维护。