They’re vs. Their vs. There

They’re

They’re is the contracted form of They are.

• They’re playing. (= They are playing.)
• They’re running. (= They are running.)

There

There is a kind of preparatory subject. It is used in sentences which say that something exists somewhere.

• There is a bridge over the river.
• There is no way out.
• There are two people in the room.

Their

Their is a possessive word like my or your.

• I have been to their home.
• I would like to buy their car.