问题 填空题

当焊接电源的输出电压随焊接电流的增加,而发生急剧下降时,称为()。

答案

参考答案:具有陡降特性

单项选择题 A1型题
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