问题
选择题
-I'm sorry , but I don't know the answer.
- _____ aren't you supposed to be an expert on this subject?[ ]
A. Why not you
B. Why not
C. Why do you
D. Why don't you
答案
答案：B
搜题请搜索小程序“爱下问搜题”
-I'm sorry , but I don't know the answer.
- _____ aren't you supposed to be an expert on this subject?[ ]
A. Why not you
B. Why not
C. Why do you
D. Why don't you
答案：B
=10m/s的初速度斜向上抛出，如图，初速度方向与水平面的夹角
，不计空气阻力，g=10m/s2，以下判断中正确的是（ ）