问题
选择题
单项选择。
—Where you from? —I from China.[ ]
A. are; is
B. is; are
C. am; is
D. are; am
答案
答案：D
搜题请搜索小程序“爱下问搜题”
单项选择。
—Where you from? —I from China.[ ]
A. are; is
B. is; are
C. am; is
D. are; am
答案：D
所有碳原子一定在同一平面上
至少有16个原子共平面