G90指令主要用于轴类零件的外圆、内圆和锥面的加工。
查看答案
G94指令适用于加工圆柱端面或角度大的圆锥面。
A. 对
B. 错
2.I wonder why Jenny ________us recently.We should have heard from her by now.
A. hasn’t written
B. doesn’t write
C. won’t write
D. hadn’t written
3.—When will you come to see me,Dad?I will go to see you when you ________ the training course.
A. will have finished
B. will finish
C. are finishing
D. finish
4.—How long ________ at this job? —Since 1990.
A. were you employed
B. have you been employed
C. had you been employed
D. will you be employed
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