改错 Who's book is this?

改错 Who's book is this? 改错Who's book is this?（） who is this book?it’s hers改错 who's book is this哪个词错了 改错：is this book your? who's green coat is this?怎样改错!急 Excuse me,who's is this eraser?改错 who is book is this 哪里错 this is his the best book改错 This a book is good 怎么改错 改错This is a expensive book 改错题：This is a my book.