题干
--I haven’t heard from John for a long time.
--What do you suppose to him?
A：was happening
B：to happe
C：has happened
D：had happened
答案(点此获取答案解析）
C
A：was happening
B：to happe
C：has happened
D：had happened
的三条棱
、
、
所在直线的距离相等的
，下列说法中正确的是（ ）