a quick grammar lesson

they’re, their and there:
they’re=contraction of they are. (They’re moving tomorrow.)
their=a form of the possessive case of they used as an attributive adjective, before a noun (Their boxes are on the sidewalk.)
there=–adverb

1.
in or at that place (opposed to here): She is there now.

2.
at that point in an action, speech, etc.: He stopped there for [...]