There, their, they're
(adv) in or at a place; referring to a place or location
Their: Possessive pronoun of third-person they.
They're: Contraction of they are or there are.
Their lunch is ready.
NOT: There lunch is ready.
They're a disorganized group.
NOT: There a disorganized group
NOT: Their a disorganized group
It's about time they went there.
NOT: It's about time they went their.
NOT: It's about time they went they're.
If you wrote there, will the sentence still make sense if you replace it with here? If so, you're using it correctly.
It's about time they went here.
If you chose their, will the sentence still make sense if you replace it with our? If so, you've chosen the correct word.
Our lunch is ready.
If you used they're, will the sentence still make sense if you replace it with they are? If so, you're on the right track!
They are a disorganized group.
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