Differences between Their and They're
Contents
Comparison Article[edit]
In the English language, the words "their" and "they're" constitute a pair of homophones that are frequently confused in written communication. Although they are pronounced identically in most dialects of English, they belong to different grammatical categories and follow distinct syntactic rules. "Their" is a possessive adjective, whereas "they're" is a contraction of a pronoun and a verb. Distinguishing between these forms is a standard component of English orthography and grammar instruction [1].
Their vs. They're[edit]
The primary difference lies in the relationship the words establish between the subject and the rest of the sentence. "Their" indicates ownership or association, while "they're" describes a state of being or an action performed by a plural subject.
Comparison table[edit]
| Category | Their | They're |
|---|---|---|
| Grammatical form | Possessive adjective | Contraction |
| Components | Root word (possessive) | They + are |
| Function | Indicates ownership or association | Acts as a subject and verb |
| Substitution test | Can be replaced by "our" or "my" | Can be replaced by "they are" |
| Sentence position | Precedes a noun or another adjective | Often begins a clause or precedes a verb |
| Historical origin | Old Norse (þeira) | Old English (þā) + (earun) |
| Formal usage | Acceptable in all writing styles | Often avoided in formal academic prose |
Grammatical functions[edit]
Usage of "their"[edit]
"Their" is the possessive form of the third-person plural pronoun "they." It functions as an adjective that modifies a noun by indicating that the noun belongs to a group. For example, in the sentence "The students forgot their books," the word "their" clarifies that the books belong to the students.
Historically, "their" entered the English language from Old Norse roots during the Middle English period, eventually displacing the Old English possessive "hiera" [2]. In contemporary usage, "their" is also employed as a singular possessive for individuals who prefer gender-neutral pronouns or when the gender of a person is unknown. Major style guides, including the Associated Press (AP) and the American Psychological Association (APA), have adopted the singular "their" to improve clarity and inclusivity in writing [3].
Usage of "they're"[edit]
"They're" is a phonetic shortening of the phrase "they are." The apostrophe in the word functions as a placeholder for the omitted letter "a" in the verb "are." This form is used when "they" is the subject of a sentence followed by a predicate. An example is "They're going to the park," where "they" is the subject and "are going" is the present continuous verb.
Linguistic constraints prevent "they're" from being used at the end of a sentence. While a speaker might say "I know where they are," they cannot say "I know where they're." This is due to the stress patterns of English, which require a full verb form in certain terminal positions [4].
Distinguishing methods[edit]
A common technique for identifying the correct form involves the substitution test. If a writer can replace the word with "they are" and the sentence remains grammatically sound, "they're" is the correct choice. If the sentence requires a word indicating possession, "their" is used. For instance, in the sentence "They're at their house," the first instance passes the "they are" test, while the second does not [5].
References[edit]
[1] Crystal, D. (2003). "The Cambridge Encyclopedia of the English Language." Cambridge University Press. [2] "Their (adj.)." Online Etymology Dictionary. Retrieved February 13, 2025. [3] American Psychological Association. (2020). "Publication Manual of the American Psychological Association" (7th ed.). [4] Huddleston, R., & Pullum, G. K. (2002). "The Cambridge Grammar of the English Language." Cambridge University Press. [5] Garner, B. A. (2016). "Garner's Modern English Usage." Oxford University Press.
