Understanding "They", "Their", "Theirs", and "Them" in English Grammar

In English, when referring to more than one person in a general or specific context, the pronouns "they", "their", "theirs", and "them" are of primary importance. These terms offer both inclusivity and specificity in various scenarios. This article breaks down the nuances of these four pronouns.

1. What are "They", "Their", "Theirs", and "Them"?

  • They: A subject pronoun referring to two or more people or things.

    Example: They are my friends.

  • Their: A possessive adjective indicating that something belongs to or is related to the people or things previously mentioned.

    Example: That's their dog.

  • Theirs: A possessive pronoun suggesting ownership or a relation to two or more people.

    Example: The bigger cake is theirs.

  • Them: An object pronoun referring to two or more people or things.

    Example: I saw them at the park.

2. What Tense Uses "They", "Their", "Theirs", and "Them"?

These pronouns are not restricted by tense. They can be featured in sentences in the past, present, or future.


  • They visited Rome last year. (Past)
  • Their house is on Elm Street. (Present)
  • I will give the books to them tomorrow. (Future)

3. How to Use "They", "Their", "Theirs", and "Them" in Sentences:

  • They: Always functions as a subject.

    Example: They like hiking.

  • Their: Denotes possession or association.

    Example: Their solution was ingenious.

  • Theirs: Stands alone to signify possession.

    Example: The choice is theirs.

  • Them: Operates as an object (either direct or indirect).

    Example: You can trust them.

4. The Difference Among "They", "Their", "Theirs", and "Them":

  • They: Subject pronoun.

    Example: They are on a vacation.

  • Their: Possessive adjective.

    Example: I like their approach to the problem.

  • Theirs: Possessive pronoun.

    Example: This idea was theirs from the beginning.

  • Them: Object pronoun.

    Example: The coach selected them for the match.

5. Cases Where "They", "Their", "Theirs", and "Them" Shouldn't Be Used:

  • Using "them" as a subject:

    Incorrect: Them are responsible. Correct: They are responsible.

  • Using "they" as an object:

    Incorrect: I gave the tickets to they. Correct: I gave the tickets to them.

  • Using "theirs" with a noun:

    Incorrect: That is theirs mistake. Correct: That is their mistake.


6. Practice They/Their/Theirs/Them Exercises 

What are the differences among "They/Their/Theirs/Them" in English? This test was designed for you to practice "They/Their/Theirs/Them". The test has 20 questions. Before taking the test, please read the following tips about "They/Their/Theirs/Them".


They is a Subject Personal Pronoun.

Ex: They can play guitar.


Their is a Possessive Adjective.

Ex: These are their guitars.


Theirs is a Possessive Pronoun.

Ex: That guitar is theirs.


Them is an Object Pronoun.

Ex: I met them at a party last night.

To wrap up, the pronouns "they", "their", "theirs", and "them" hold a pivotal position in the English language, serving as tools to reference multiple entities, whether people or things. Grasping the distinctions and applications of these pronouns can greatly enhance one's fluency and precision in English communication.

Now You'll take a "They/Their/Theirs/Them" test.