受主力作用杆件的接头应采用对接焊缝,焊缝厚度不应大于被焊接构件的最小厚度。 发布时间:2017-06-27 18:10 │ 来源:www.tikuol.com 题型:判断题 问题: 受主力作用杆件的接头应采用对接焊缝,焊缝厚度不应大于被焊接构件的最小厚度。
题型:判断题 —Our environment is getting worse than before. —You're right. But people have done more and more useful things to protect (保护) the earth since Earth Day _____. [ ]A. is started B. was started C. has started 查看答案