【单选题】This is one of the best books__________. A.that have ever been written B.that has ever been written C.that has written D.that have written
A.
that have ever been written
B.
that has ever been written
【简答题】综合布线系统的基本含义是什么?与传统布线相比,具有哪些特点?
【简答题】拉深的变形程度用什么来表示?什么是极限拉深系数?哪些因素影响极限拉深系数?
【单选题】2011年之前乒乓球是什么材料做的?( )
【简答题】影响极限拉形系数的因素:_____________、包角大小和摩擦系数。
【单选题】The English of this composition is excellent .He _______ it himself. A ) can’t have written B ) won’t have written C ) mustn’t have written D ) shouldn’t have written
D.
shouldn’t have written