In proofreading your work, it's never a bad idea to slow down and give a little extra attention to these troublemakers.
They're: is a contraction used in place of 'they are.'
The apostrophe denotes the place from which the 'a' in 'are' has been removed to form the contraction.
Their: is possessive.
It indicates ownership by them.
There: generally refers to location (*).
You can easily remember it because it contains the word 'here,' which also deals with location.
.(*) Of course, there are other uses for 'there.' See? There's another one! If you want to know more, check it out at dictionary.com.
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