清管球由氯丁橡胶制成,一般壁厚为()mm,注需水使用 A.20~40 B.30~ 发布时间:2017-09-16 10:34 │ 来源:www.tikuol.com 题型:单项选择题 问题: 清管球由氯丁橡胶制成,一般壁厚为()mm,注需水使用A.20~40 B.30~50 C.40~60 D.50~70
题型:单项选择题 Sometimes _____ English is quite different from _____ English in many ways.A. speaking, writing B. spoken, written C. speaking, written D. spoken, writing 查看答案