This is a book.对book 提问时what is it 对,还是what is this?

This is a book.对book 提问时what is it 对,还是what is this? what is it it is a book 对 ? 还是it is the book对? This is a book.对a book进行提问 对This book is eight dollars 提问 This is my book.对my提问 this is a book 提问 this is my English book对my English book提问 This is my book .对book提问如何做 This is a book,It's an English book.What's this?急. This is s book.(a book提问) This is a book (对a What is this in English it is a book What colour are they th