The foxes hid themselves in the places (that)couldn't be found.
问题描述：
The foxes hid themselves in the places (that)couldn't be found.
为何用括号中词?
为什么不用where?
答
括号中的that是可以不要的,
that只是指代前面的place
后面的couldn't be found 是对place的 补充说明
是一个非限制式从句