选用何种钻床夹具,决定于工件上被加工孔的分布情况,有()等主要类型。
A.固定式
B.回转式
C.移动式
D.翻转式
参考答案:A, B, C, D
Not until he called the secretary three times ______ that the manager went to an important meeting. [ ]
A. did he tell
B. he told
C. was he told
D. he was told
学校和监护人承担法律责任的归责原则不同。学校承担的是过错责任,以下哪种情况下学校才能承担责任:()
A.只有在学校存在过错的情况下
B.只有在被家长告上法庭的情况下
C.只有在学生受到伤害的情况下