There, Their and They're: Grammar Guide
There, Their and They're
There denotes a place and means in, at, or to that place.
- I want to go over there for a better view of the stage.
- Could you please place the signs over there?
- There is a very good reason for his persistence.
There is a determiner belonging to them, a possessive pronoun.
- Are you going in their car?
- I want to be a part of their team.
- Their song was the best of the set.
They're is the contraction of they are. If you can replace they're with "they are", then you have used the correct homonym.
- They're going to go to the ballpark at 1:00.
- I want to see what they're doing after the game.
- They said that they're going to a pub.