What's wrong with this book and why?

Yes, anything-who is it? This is equivalent to replacing it with this book.

Whose computer is that? Whose computer is that? Whose soldiers are they? Whose sweaters are these? Whose is used to ask questions about possessive pronouns and possessive cases of nouns:

1. Ask possessive pronouns of adjectives, such as: These are my bananas. Whose bananas are these?

2. ask the subject pronoun of the part of speech, such as: that bedroom is mine. Whose bedroom is that? Hers is in the classroom. Who is in the classroom?

3. Ask about the possessive case of nouns (excluding the possessive case formed by of). For example, these are twin bags. Whose bags are these? Tom's mother is a good teacher. Whose mother is a good teacher?

4.which can ask questions about adjectives like mine, yours, ours, theirs, Kate's, etc. The word order is:

These are their sweatshirts. These are their sweatshirts.

Whose sweaters are these? Whose jerseys are these?

(Asking questions about attributes)

Whose can also ask questions about possessive pronouns or nouns such as mine, yours, ours, theirs and Kate's.

This shirt is his. This shirt is his.

Whose shirt is this? Whose shirt is this?

(Asking questions about predicative words)

Ask questions about the underlined part

Those are her pants.

Whose pants are those? (attributive of interrogative sentence)

That cup is mine.

Whose cup is that? (questionnaire)

Ensure the correct rate and hope to adopt it.

If in doubt, please ask.