当钢轨出现波磨、鱼鳞裂纹等伤损时,应及时进行()打磨。 A.预防性 B.周期性 C. 发布时间:2019-03-10 04:15 │ 来源:www.tikuol.com 题型:单项选择题 问题: 当钢轨出现波磨、鱼鳞裂纹等伤损时,应及时进行()打磨。A.预防性B.周期性C.修理性D.临时性
题型:单项选择题 ________ I'm going to visit my families.[ ]A. Last morning B. Yesterday C. Tomorrow D. Today 查看答案
题型:单项选择题 A few minutes earlier, and you would have seen the NBA star. But you ________. [ ]A. didn't come B. don't comeC. haven't come D. won't come 查看答案