Repost (by popular request)
Some people have trouble distinguishing between these three words.
A quick way to remember the difference is to memorize these (very short) sentences:
That’s their house (it belongs to them). They live there (at that place). They’re nice (they are nice).
For the more formal explanations, see below.
Their is the possessive determiner. It means belonging to them.
(Note: to pluralize ‘their’, just add an ‘s’, as in: that is theirs. “Theirs” is a possessive pronoun. No need for an apostrophe.)
There is an adverb with several uses.
1) in, at or to that place or position.
2) on that issue.
3) used in attracting attention to someone or something.
4) (there is/are) used to indicate the fact or existence of something.
They’re is the contraction of ‘they are’.
I hope that helps clear up a little confusion on that issue.
Christine – guest blogger
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