in which 用法,求详解
问题描述：
in which 用法,求详解
The time will come ______ man can fly to outer space freely.
A.that B.when C.in which D.which
答
应该选B.when
in which 用法,求详解
The time will come ______ man can fly to outer space freely.
A.that B.when C.in which D.which
应该选B.when