these ancient indians used to live in what is now a part of ...为什么用what 而不用which?
问题描述：
these ancient indians used to live in what is now a part of ...为什么用what 而不用which?
答
这是宾从，改成先行词加which的定从可以，the place which
答
还没有一个实体的时候用what指代一个实体.
已经有了几个实体的时候,用which指代其中一个实体.