Choose the correct pronoun to complete the following
This book is _____ , and that one is mine.

Question

Accepted Answer

To complete the sentence "This book is _____ , and that one is mine," the correct pronoun is "yours," which is Option 3. Here's a detailed explanation of why this is the correct choice and why the other options are incorrect:

1. **Explanation for Option 3 ("yours"):**
   - "Yours" is a possessive pronoun that indicates ownership or possession. In the context of the sentence, it is used to show that the book belongs to the person being addressed. The sentence structure "This book is yours" is grammatically correct and clearly conveys that the book in question belongs to the other person, while the speaker owns the other book mentioned ("that one is mine").

2. **Why Option 1 ("our book") is incorrect:**
   - "Our book" is a possessive phrase that implies joint ownership between the speaker and at least one other person. However, the sentence structure requires a pronoun, not a noun phrase. Additionally, the sentence contrasts two separate possessions, so "our book" does not fit the context of individual ownership.

3. **Why Option 2 ("your") is incorrect:**
   - "Your" is a possessive adjective, not a pronoun. It needs to be followed by a noun to complete the phrase (e.g., "your book"). In the sentence, a standalone possessive pronoun is required to match the structure and meaning, making "your" an unsuitable choice.

4. **Why Option 4 ("yours book") is incorrect:**
   - "Yours book" is grammatically incorrect because "yours" is a possessive pronoun and should not be followed by a noun. The correct usage is to use "yours" alone to indicate possession, without adding the noun "book" after it.

In summary, Option 3 ("yours") is the correct choice because it is the appropriate possessive pronoun that fits the sentence structure and meaning, indicating that the book belongs to the person being addressed. The other options do not meet the grammatical requirements or the context of the sentence.