管线组装焊接时,管子对接的错口公差不应超过壁厚的()。 A.20% B.5% C.2 发布时间:2017-09-05 03:53 │ 来源:www.tikuol.com 题型:单项选择题 问题: 管线组装焊接时,管子对接的错口公差不应超过壁厚的()。A.20%B.5%C.2%D.10%
题型:单项选择题 John and I _____ friends for eight years. We first got to know each other at a Christmas party. But we ____ each other a couple of times before that.A.had been; have seenB.have been; have seenC.had been; had seenD.have been; had seen 查看答案