题干
I to Canada twice. It's so beautiful.
A：won't go
B：don't go
C：have gone
D：have been
答案(点此获取答案解析）
D
I to Canada twice. It's so beautiful.
A：won't go
B：don't go
C：have gone
D：have been
的三条棱
、
、
所在直线的距离相等的