题干
— Tom, who taught Chinese before you came to China?
— Nobody. I learned it by .
A：your; myself
B：his; himself
C：you; myself
D：him; himself
答案(点此获取答案解析）
C
定义域为
，且对任意
，
恒成立.则下列选项中不恒成立的是（ ▲ ）
