"This is my phone" and "This phone is mine" mean the same thing — but my and mine are never interchangeable. One always sits in front of a noun. The other always stands completely alone.
What you'll learn
Every possessive word in English does one of exactly two jobs: it either sits directly in front of a noun ("my car," "her office"), or it stands completely alone, with no noun after it at all ("It's mine," "That desk is hers").
Ask yourself one question every time: is a noun coming right after this word? If yes, you need the form that goes with a noun. If the possessive word is the whole answer by itself, you need the standalone form.
These two roles are sometimes called "possessive adjective" (in front of a noun) and "possessive pronoun" (standing alone) — the names describe the job each form does, not two random word lists to memorize separately.
my → mine. Before a noun: "my keys." Standing alone: "They're mine."
your → yours. Before a noun: "your seat." Standing alone: "Is this seat yours?"
her → hers. Before a noun: "her office." Standing alone: "That desk is hers."
our → ours. Before a noun: "our flight." Standing alone: "This gate is ours."
their → theirs. Before a noun: "their luggage." Standing alone: "That suitcase is theirs."
Notice the pattern: every pair adds -s (or changes shape slightly) to make the standalone form. Except one — see below.
his does something none of the others do: it's the same word in both jobs. "This is his laptop" (before a noun) and "This laptop is his" (standing alone) both use exactly the same word, his. There is no separate "his's" — don't invent one.
its follows the my/mine pattern in only one direction: it goes before a noun constantly ("The app updated its icon," "The company changed its logo"), but it almost never stands alone in natural English. If you mean "belonging to it," you normally repeat the noun or rephrase the sentence instead — a standalone its just doesn't come up in everyday speech or writing.
You might also see my, your, his, her, its, our, and their called possessive determiners in a grammar book or app — that's a more modern grammatical term for the exact same words doing the exact same job: sitting in front of a noun. Possessive adjective and possessive determiner both point at this same word set.
mine can't sit directly before a noun — that spot always takes the adjective form, my.
my can never stand alone at the end of a sentence. Without a noun right after it, you need the pronoun form, mine.
her only works directly before a noun (her desk); standing alone needs the -s form, hers.
yours already means "belonging to you" all on its own — don't add a noun right after it too.
"Hi, someone found this backpack near gate 12 — is it yours?"
"Let me check... no, that's not my bag. Mine is black with a red strap."
"Okay. And this laptop sleeve — any idea whose it is?"
"Actually, yes, that one's ours. My husband left it on the seat."
"Great, I'll grab your husband's ID number and you can take it."
Exercise 1 · Choose the correct form
Complete the sentence: "This is ___ badge."
Exercise 2 · Choose the correct form
Complete the sentence: "This badge is ___."
Exercise 3 · Choose the correct form
Complete the sentence: "That car outside is ___."
Exercise 4 · Choose the correct form
Complete the sentence: "We already packed ___ suitcases."
Exercise 5 · Real-life scenario
A barista points to a receipt left on the counter and asks the next customer: "Excuse me, is this ___?"
Exercise 6 · Real-life scenario
A coworker holds up a laptop bag from the shared desk and asks whose it is. You say: "Yes, that's ___."
Exercise 7 · Choose the correct form
Complete: "That's not my jacket on the chair — it's ___." (it belongs to Marcus)
Exercise 8 · Sort into groups
0 / 8 sorted
Exercise 9 · Build the sentence
Exercise 10 · Build the sentence
Exercise 11 · Build the sentence
Exercise 12 · Rewrite the sentence
Rewrite so the possessive word stands alone, with no noun after it: "This is my suitcase."
Exercise 13 · Rewrite the sentence
Rewrite so the possessive word comes directly before the noun "schedule": "This schedule is theirs."
Exercise 14 · Fix the mistake
Fix the mistake: "This is mine car."
Exercise 15 · Fix the mistake
Fix the mistake: "This raincoat is your."
Exercise 16 · Complete the sentence
Complete with one word: "The company just updated ___ website."
Five mixed questions to check what stuck.
Question 1 / 5
Score: 0/0
Complete: "Whose bag is this?" "It's ___."
Possessive Pronouns
Learn the six standalone possessive pronouns — mine, yours, his, hers, ours, theirs — how they replace a whole "my/your + noun" phrase, why none of them ever takes an apostrophe, and why "its" doesn't work the same way.
Subject vs Object Pronouns
Learn when to use subject pronouns like I, he, and they, and when to switch to object pronouns like me, him, and them — based on where the pronoun sits in the sentence.
Personal Pronouns
Learn the seven subject pronouns — I, you, he, she, it, we, they — including singular "they" and how English uses "it" for weather, time, and situations.
Reflexive Pronouns
Learn the eight English reflexive pronouns — myself, yourself, himself, herself, itself, ourselves, yourselves, themselves — how to use them for reflexive meaning and emphasis, and the overcorrection mistake to avoid.