your (you're)

Which word you choose-their, they're, or there-changes meaning instantly. One shows possession, one contracts they are, and one points to place or introduces existence. A few quick tests and a handful of rewrites fix most errors.

Below are clear rules, tone tips for work/school/casual writing, many real sentences (including The Smiths example), step-by-step fixes, memory tricks, and ready-to-use practice items.

Quick answer

Use their for possession, they're for they are, and there for place or existence.

their = possessive (their keys, their plan)
they're = contraction of they are (they're late = they are late)
there = place or existence (over there / there is a problem)

Core explanation: what each word does

Their is a possessive adjective that modifies a noun: their car, their idea, their jackets. If you can swap in "our" or "the Smiths'" and it still makes sense, use their.

They're is a contraction of they are. Expand it: if "they are" fits, use they're. There is either an adverb of place (over there) or a dummy subject introducing existence (There is a solution).

Test 1 (possession): Replace with a possessive (the Smiths') → their.
Test 2 (contraction): Replace with "they are" → they're.
Test 3 (location/existence): If it points to place or starts "there is/are" → there.

Usage: The Smiths left their keys on the table. (their = possession)
Usage: They're going to be late if they don't leave now. (they're = they are)
Usage: Put the boxes over there. There are too many to carry. (there = place / existence)

Real usage and tone: formal vs casual choices

Contractions like they're are fine in casual and most workplace writing. For formal essays and many business reports, prefer the expanded form or recast the sentence (The team is expected to arrive late).

There is usually the only grammatically correct choice for location or existence. If all three forms appear close together, read the sentence aloud to check meaning.

Casual: contractions and short sentences are natural-"They're bringing dessert."
Work: contractions are usually acceptable in email; avoid them in formal reports unless your style guide allows contractions.
School: follow your instructor-many prefer no contractions in essays.

Work - Usage: They're prepared to answer questions after the presentation. (acceptable)
Formal report: The contractors are prepared to address outstanding items. (prefer spelled-out form)

How to fix your sentence (step-by-step)

Checklist: 1) Is the word followed by a noun? Try their. 2) Can you expand it to "they are"? Use they're. 3) Is it a location or introducing existence? Use there. Read the sentence aloud and apply these tests.

If tests leave you unsure, rewrite: add the missing noun, expand the contraction, or move phrases that create confusion.

Quick substitution test: replace with they are / the Smiths' / over there and see which reads naturally.
If two choices seem to fit, rewrite: "They are late" → "They will arrive late."

Rewrite:
Wrong: The Smiths left they're keys at home. →
Fixed: The Smiths left their keys at home.

Examples you can copy: common wrong/right pairs

Six frequent wrong/right pairs. Read the wrong sentence, then the corrected version. Swap subjects and objects (students, colleagues, friends) to create more examples.

Wrong: The Smiths left they're keys at home.
Right: The Smiths left their keys at home.
Wrong: Their going to the party tonight, right?
Right: They're going to the party tonight, right?
Wrong: They're dog is really friendly.
Right: Their dog is really friendly.
Wrong: I left my notebook over their.
Right: I left my notebook over there.
Wrong: Their is no reason to panic.
Right: There is no reason to panic.
Wrong: Are you sure they're jacket fits?
Right: Are you sure their jacket fits?

Work, school, and casual examples (copy-paste ready)

Short, clear sentences for team messaging, assignments, and texts. Tone varies, but grammar rules remain the same.

Work: Please upload their final drafts to the shared folder by 5pm.
Work: They're presenting the results at the meeting this afternoon.
Work: Put the agenda over there so everyone can see it when they arrive.
School: Their hypothesis was supported by the data in the second experiment.
School: Are they sure they're ready for the exam?
School: Leave your backpack over there, near the lab bench.
Casual: I think they're joking about the surprise party.
Casual: Did you leave your charger there or at home?
Casual: Their playlist always has the best songs.

Try your own sentence

Test the whole sentence, not just the word. Context usually reveals the correct choice.

Rewrite help: make your sentence less ambiguous

If tests still leave you unsure, rewrite to remove the ambiguous word. Adding a noun, expanding a contraction, or recasting the phrase prevents the error and improves clarity.

These rewrites are useful in headings, captions, and places readers scan quickly.

Add the noun: change their → their keys or their plan when the noun is implied but missing.
Expand contractions: use they are in formal writing or to check correctness.
Recast location: replace there with in that place or at that location when helpful.

Rewrite:
Original: The Smiths left their keys. →
Rewrite: The Smiths left their keys on the kitchen counter by the sink.
Rewrite:
Original: They're going to fix the printer. →
Rewrite: They are going to fix the printer and should be back within twenty minutes.
Rewrite:
Original: There are problems with their schedule. →
Rewrite: Conflicts in their schedule mean we'll need to reschedule the meeting.

Memory tricks you can use right away

Pick one trick and use it until it becomes automatic. Two quick favorites work well under pressure: the replace test and one-word cues for each form.

The one-word cues: their → heir (ownership), they're → they are (contraction, has an apostrophe), there → here (location). Say the cue when you hesitate.

Replace test: substitute "they are" or a possessive to see which fits.
Heir mnemonic: their contains the sound heir → possession.
There = here: if you can swap here for there and it makes sense, it's location.

Usage: Heir trick: Their = ownership → "their house" (like an heir inherits a house).

Hyphenation, spacing, and punctuation notes

Apostrophes belong directly next to contractions: they're, not they 're. Don't add a space before an apostrophe or between letters removed by it.

Spacing around commas and periods follows normal rules-no extra space before punctuation. When you expand contractions, mind subject-verb agreement: they are must match the verb that follows.

Never add a space before an apostrophe: correct = they're, not they 're.
Hyphenation rarely affects their/they're/there; use hyphens to clarify compound modifiers (their well-being).

Usage: Wrong spacing: they 're going to arrive. Right spacing: they're going to arrive.

Grammar deep-dive: why these errors happen

Their is a determiner that must modify a noun. They're combines a pronoun and a verb. There either signals place or serves as an existential subject. Identifying each role makes parsing complex sentences easier.

In sentences with multiple clauses, ask which word modifies which noun and which clause contains the verb. Break long sentences into shorter ones to test each word's role.

Possessive test: if the word modifies a noun (their answer), it's their.
Contraction test: if the word is subject-plus-verb (they're = they are), it's they're.
Existential test: if it introduces "there is/are" or points to location, it's there.

Usage: Complex sentence: There are students who forgot their books because they're late to class. (there = existence; their = possession; they're = they are)

Similar mistakes to watch for

If you confuse their/they're/there, you probably mix up your/you're, it's/its, and to/two/too. Use the same substitution tests for these pairs.

your vs you're - your = possession; you're = you are.
it's vs its - it's = it is or it has; its = possessive.
to vs too vs two - to = preposition/infinitive; too = also/excessively; two = number 2.

Usage: Wrong: Your going to love their new song.
Right: You're going to love their new song.

FAQ

Is "their" ever correct before a verb?

No. Their always modifies a noun. If a verb follows, check whether you meant they're (they are). For example, "Their leaving at 5" should be "They're leaving at 5."

Which is correct: "The Smiths left their keys" or "The Smiths left they're keys"?

The correct sentence is "The Smiths left their keys." Their shows possession; "they're" expands to "they are" and doesn't make sense before a noun.

Can I use "they're" in formal writing?

In formal academic or technical documents, avoid contractions and write "they are." In many business emails and informal workplace contexts, "they're" is acceptable-follow your organization's style guide.

How do I quickly check while proofreading?

Use the replace-test: substitute "they are" (contraction), a possessive like "the Smiths'" (their), or "here/at that location" (there). If one replacement reads naturally, that's the correct choice.

Are there tools that fix their/they're/there automatically?

Yes-grammar checkers catch many instances, but always read suggestions yourself. Tools can miss context or creative uses. For fast checks, paste your sentence into a checker or use the substitution tests above.

Want to double-check a sentence?

When you hesitate between their, they're, and there, paste the full sentence into a checker and read the suggested change aloud. That catches many errors faster than guessing.

Try checking one sentence now with the widget above to see suggested fixes and a short explanation as you edit.