There, their and they’re are homophones (where they are pronounced the same but have different spellings and meanings). It can be tricky to know which to use and when.

There

There is potentially the most complex version as it can be an adjective, noun/pronoun or adverb. In this way, there can be used to describe, introduce or represent a location.

There is considered an adjective when it modifies a noun. Simply, this means there will follow the noun and will be used in a sentence such as, She is there to answer questions. She is the noun, there follows as an adjective.

As a noun, there represents a specific place, Just place it over there. It’s assumed that the other person knows where there is, perhaps with the addition of a gesture, so the place doesn’t require any further explanation.

To use there as a pronoun is very similar, and will replace the noun. E.g. Hey there!

As an adverb, there is the opposite of here. This spelling even contains the term here, making it easier to remember. In this way, there always represents a location. E.g. I was asked to go there.

Their

Their is a possessive pronoun and shows ownership. In a similar way to your, their represents belonging and is the possessive form of they. This means it will always be used in relation to people or living things.
E.g. It’s their job. We’re their friend.

They're

They’re is a contraction. The full phrase would be they are or they were. This helps when deciding if this is the right word choice: insert the full form into the sentence to determine if it sits correctly. This is the same process as considering you’re.
E.g. They’re lovely people.

Take away

  • Consider the sentence you are trying to write. Are you addressing a place, person or showing ownership?
  • There is the most complex, but links to location. Remember: it is the opposite of here.
  • Their is possessive so represents ownership. Remember: does this directly link to a person or living thing?
  • They’re is a contraction. Remember: use the full phrase they are in the sentence to determine its suitability.