最早将专题研讨班引入大学教学中的人是()。
A、弗兰克
B、凯勒
C、格斯纳
D、赫尔巴特
参考答案:C
Tom has been out of work for two years, so he has difficulty _____. [ ]
A. earning living
B. earning his living
C. to earn livings
D. to earn his living
设计说明部分审核的关键点()
A.总体方案
B.电源方案
C.天线的使用
D.接地防雷方案