There, their, and they’re sound similar but have different jobs in a sentence. There most often points to a place or introduces that something exists. Their shows possession for the pronoun they. They’re is a contraction meaning they are, so it always relates to an action or a state.

Use there to talk about location: it answers where. Use there to introduce or point out existence with sentences like There is or There are. In these existential sentences, there is not the subject; it is a placeholder that lets you present new information smoothly.

Rule	Example
Use there for location	Put it over there.
Use there with be to introduce existence	There are two options.
Use there with singular and plural be correctly	There is a problem. There are problems.

Use their to show that something belongs to them. Their can modify a noun directly and does not change for gender. It can refer to a group of people, or to one person when you do not know the person’s gender or when the person uses they.

Rule	Example
Use their before a noun to show possession	Their car is outside.
Their can refer to one person in singular they usage	Someone left their phone.
Their can refer to mixed or unspecified gender groups	Each student should bring their ID.

Use they’re only when you can replace it with they are. Because it is a contraction, it normally fits informal or neutral writing; in very formal writing, you may prefer they are. If the sentence does not describe what they are or what they are doing, they’re is usually wrong.

Rule	Example
Use they’re when it equals they are	They’re ready now.
If you cannot expand to they are, do not use they’re	Incorrect: They’re house is big. Correct: Their house is big.
Prefer they are in very formal writing if needed	They are responsible for the results.

A reliable way to choose the correct form is to test what the word must mean in your sentence. If you mean a place or an existence statement, choose there. If you need a possessive determiner before a noun, choose their. If the phrase can become they are, choose they’re.

These three forms belong to different grammar categories, which is why they cannot substitute for each other. There is an adverb of place or an introductory word in existential clauses. Their is a possessive determiner that modifies a noun. They’re is a contracted verb phrase combining a subject pronoun and the verb be.

Word/Phrase	Definition	Example
there	location word or existential starter	There is a café nearby.
their	possessive determiner meaning belonging to them	Their café is busy.
they’re	contraction of they are	They’re busy today.

In There is and There are sentences, the true subject comes after the verb, and there simply introduces it. Use this pattern to present new information, especially in speech and writing. Agreement typically follows the noun that comes after the verb, although informal speech sometimes uses There’s with plurals.

Rule	Example
Match be to the noun after it in careful writing	There are many reasons.
Use this pattern to introduce new information	There is a new policy.
Informal speech may use There’s with plurals	There’s two tickets left.

Their and they’re are both used with singular they. This use is common and accepted in modern English for a person whose gender is unknown, irrelevant, or nonbinary. The verb agreement remains plural in form, so you still say they are and therefore write they’re.

Rule	Example
Use their with singular they to show possession	If a customer calls, take their name.
Use they’re because singular they still takes are	If someone is late, they’re probably stuck in traffic.
Use their for known individuals who use they pronouns	Jordan forgot their keys again.

When you hesitate, focus on what the sentence must communicate. If you can point to a place, there is the only choice. If a noun needs an owner, their is the only choice. If you need a verb phrase describing them, they’re is the only choice.

They’re uses an apostrophe because letters are missing from are. Their and there never take an apostrophe. In careful writing, avoid creating a possessive with an apostrophe for pronouns, since standard pronoun possessives do not use one.