The difference between "this is my book" and "this book is mine" lies in the use of a possessive adjective versus a possessive pronoun. Both constructions indicate ownership, but they are used in slightly different grammatical contexts.
1. Possessive Adjectives
"This is my bicycle" uses a possessive adjective ("my"). Possessive adjectives are used before a noun to show ownership or possession. They tell us who owns the item.
Possessive adjectives include: my, your, his, her, its, our, their.
2. Possessive Pronouns
"This bicycle is mine"shows different construction. Possessive pronouns stand in place of a noun and indicate ownership. Unlike possessive adjectives, they do not precede a noun because they effectively replace the noun.
The next survey shows the difference
1. this is my bike
2. that is yout bike
3. I go with our car to Turkey
4. do you go with your bike to the forest?
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