This is (a math) book.

This is (a math) book. 如何回答：Is this a math book ? why is a math book sad This is a book this is (his) math book 对括号部分提问 whose is this math book?(改为同义句) 就画线部分提问1.This is (a math book ).2 .Tony is my brother .3 .Th Is this a book?" "Yes,this is." This is s book.(a book提问) this is a book 提问 This is a interesting book Why is a math book sad?英语谜语