There can be used in several different ways. Below are two of the most common usages.
1. As an adverb, there means “in” or “at that place.” Think of there as the opposite of here.
Example: He asked me to go there and buy candy.
2. There is also used as a pronoun introducing the subject of a sentence or clause.
Example: There are three apples on the table.
Swedish
där, dit, det, avseende
Their is a possessive pronoun and it is used to indicate ownership. It means “belonging to them.”
Examples
This is their car.
Have you met their daughter?
The trees are losing their leaves.
Swedish
deras, sin, sina
They’re is a contraction of they and are. The apostrophe replaces the missing letter.
Tip: only use they’re if you can substitute it with they are.
Examples
They’re from Canada.
Things are only impossible until they’re not.
Swedish
de är