问题描述：
of which 用法
There are over 58,000 rockey objects in space,about___ could fall down onto the earth.
A.900 of which
B.of which 900
我好想记得我们老师说过of which about
为什么
There are over 58,000 rockey objects in space,about___ could fall down onto the earth.
A.900 of which
B.of which 900
我好想记得我们老师说过of which about
为什么
问题解答：
我来补答展开全文阅读