问题 单项选择题

插齿加工过程中,消除周节累积的方法是调整分度蜗轮蜗杆啮合间隙,必要时修磨蜗轮杆,仔细研制工作台壳体上的圆锥接触面,使用锥面接触较上平面接触硬些,另外可重新()插齿刀,使误差相抵消,必要时修磨插齿刀主轴端面,凸轮轮廓和插齿刀垫,检查工件定位心轴的精度并加修正或更换新件。

A、安装

B、修改

C、换

D、改制

答案

参考答案:A

判断题
写作题

假如你是刘宁,本学期刚转学到另一个城市,不适应新环境,想给好朋友宋薇写一封邮件,要点如下:

1.询问近况,表达思念;

2.不习惯饮食和天气;

3.听课有困难;

4.没有朋友,感到孤独。

注意:

1.词数120左右。

2.可适当增加细节,以使行文连贯。

Dear Song Wei,

                                                                                 

                                                                                   

                                                                                 

                                                                                   

                                                                                   

                                                                                  

                                                                                   

                                                                                 

                                                                                  

                                                                                  

                                                                                   

Yours sincerely,

Liu Ning