题干
Don't put off today's work for tomorrow. I mean, today's work______ today.
A：may do
B：must do
C：may be done
D：must be done
答案(点此获取答案解析）
D
Don't put off today's work for tomorrow. I mean, today's work______ today.
A：may do
B：must do
C：may be done
D：must be done
且与曲线
在点
处切线垂直的直线方程是（ ）