its/it's · whose/who's · their/there/they're — English Grammar Exercises
my/mine, your/yours, their/theirs — know the difference
its/it's, whose/who's, their/there/they're
These three homophone groups are among the highest-frequency errors in all English writing — not just in learner corpora. Data from the Corpus of Contemporary American English (COCA) and the British National Corpus (BNC) shows that its/it's confusion is present in a significant proportion of informal digital texts, making it one of the most studied orthographic errors in English. For language learners, the additional challenge is that the possessives (its, whose, their) are structurally similar to each other, while the contractions require recognising elided auxiliary verbs.
its vs it's
Its (no apostrophe) = possessive adjective for things, animals, and organisations:
It's (with apostrophe) = it is / it has (contraction).
The company changed its logo. (possessive — the company's logo)
It's raining outside. (= It is raining)
It's been a long day. (= It has been)
Test: substitute 'it is' or 'it has'. If the sentence still makes sense, write it's. Otherwise, write its.
whose vs who's
Whose = possessive — asking or stating whom something belongs to:
Who's = who is / who has (contraction).
Whose jacket is this? (possessive question)
Who's coming to the party tonight? (= Who is coming)
Who's going to tell the boss? (= Who is going to)
their vs there vs they're
Their = possessive adjective (belonging to them).
There = location or existential ('there is/are').
They're = they are (contraction).
The cinema is over there. (location)
They're going to the concert tonight. (= They are going)
Common Mistakes
✗ Whose going to tell the boss? → ✓ Who's going to tell the boss?
✗ Their going to the concert. → ✓ They're going to the concert.
✗ I hope there friends save seats. → ✓ I hope their friends save seats.
Frequently Asked Questions
What is the difference between possessive adjectives and possessive pronouns?
Possessive adjectives (my, your, his, her, its, our, their) come before a noun and modify it: 'Is this your bag?' Possessive pronouns (mine, yours, his, hers, ours, theirs) stand alone and replace the noun to avoid repetition: 'I forgot my umbrella. Can I borrow yours?' The key test: if a noun follows immediately, use the adjective form. If the noun is omitted, use the pronoun form. Note that 'his' and 'its' serve as both adjective and pronoun.
What does 'a friend of mine' mean, and why not 'a my friend'?
'A friend of mine' is the double possessive (or post-genitive) construction meaning 'one of my friends'. English does not allow a possessive adjective after an indefinite article: 'a my friend' is ungrammatical. The pattern is: indefinite article + noun + of + possessive pronoun (mine/yours/his/hers/ours/theirs). Compare: 'I bumped into a colleague of hers' (one of her colleagues). After 'of', always use the pronoun form, not the adjective: 'of mine', not 'of my'.
What is the difference between 'its' and 'it's'?
'Its' (no apostrophe) is the possessive adjective, showing that something belongs to it: 'The company changed its logo.' 'It's' (with apostrophe) is a contraction of 'it is' or 'it has': 'It's raining' (= it is raining); 'It's been a long day' (= it has been). The test: expand the contraction. If 'it is' or 'it has' makes sense, write 'it's'. If not, write 'its'. This is one of the most common spelling errors at B1–B2 level in learner corpora.
How do I use 'own' in English — 'my own', 'on my own', or 'of my own'?
'Own' always follows a possessive adjective and adds emphasis on exclusive or personal possession. Three patterns: (1) possessive + own + noun for emphasis: 'She has her own room' (not shared); (2) on + possessive + own = alone, without help: 'He did it on his own' (never 'by his own'); (3) a/some + noun + of + possessive + own = something that personally belongs to someone: 'They want a house of their own'. Note: 'an own car' is wrong — 'own' always needs a possessive adjective before it.