Your: a possessive second-person adjective, e.g. “You left your whip at my house last night.”
You’re: a contraction of “you are,” thus creating a subject/predicate relationship in a single word. E.g. “You’re getting glitter all over me.”
Its: a possessive third-person gender-neutral adjective, e.g. “The Predator aimed its laser cannon at the Alien Queen.”
It’s: a contraction of “it is,” e.g. “It’s hard out here for a pimp.”
Their: a possessive third-person plural adjective, e.g. “Do not eat their porridge.”
They’re: a contraction of “they are,” e.g. “They’re going to break through the outer barricades and capture our flag!”
There: multi-function word, often serving as an adverb modifying the verb “to be,” e.g. “The the porta-potty is there.” Arguably, uses of “there” as a pronoun (“There are bees in here!”) or as an adjective (“William there, he enjoys a good haggis”) are really just variations on the use of “there” as an adverb. “There” could also be an interjection, e.g. “So there, biatch!”
To review:
Possessive adjectives: your, its, their
Contractions of a pronoun and a verb: you’re, it’s, they’re
Multi-purpose: there
