遮线器的作用是遮去不必要的() A.软射线 B.漏射线 C.散射线 D.α射线 E. 发布时间:2017-04-25 22:26 │ 来源:www.tikuol.com 题型:单项选择题 A1/A2型题 问题: 遮线器的作用是遮去不必要的()A.软射线B.漏射线C.散射线D.α射线E.原发X线
题型:单项选择题 A1/A2型题 Being afraid of making mistakes, the little boy _____ answer his teacher's question.A. does dare B. doesn't dare C. daren't to D. not dare to 查看答案