Holy Moly, Batman! Writers Bewair, Bewear, Beware. The problems of their, there, and they're.
OK, by popular demand, here's the skinny on how to get this straight.
THERE is an indication of a place: Put the basket there. Go over there.
It can also be used with a "be" verb to indicate the existence of something: There is a house in the woods.
Rarer use might be in a greeting: Hey, there.
Rarer still it's used as a soother: There, there, nothing's broken.
THEIR is a plural, possessive pronoun used for ownership by more than one: Their team always wins. We like to get their ideas.
THEY'RE is a contraction of "they are." They are foolish. = They're foolish. Usually followed by a verb, noun, or adjective: They're running late. They're clowns. Their tall. Watch out for ends of sentences; won't work: I wonder where they are. You can't say, "I wonder where they're."