It's famous for the strange shape of its tall rocks. 中shape为什么不加s

Question

外研版初二下学期第七模块第二单元 It's famous for the strange shape of its tall rocks. 中shape为什么不加s

Answer 1

这里强调的是整个石头的形状，不是指一块一块石头的样子，所以用单数

Answer 2

此处形状无需用复数，岩石的形状

Answer 3

shape是不可数名词。