教师做好教诲教学工作的前提保证和核心要求是确立不错的（）。
参考答案：学生观
I will have to call my friend Peter ________ coat I walked off by mistake yesterday. [ ]
A. in whose
B. in which
C. on which
D. with whom
C200H手持式编程器的灰色区域是（）。
A、数字键
B、清除键
C、操作键
D、指令键
