Thier vs. Their
Thierpronoun
misspelling of their
Theirdeterminer
Belonging to, from, of, or relating to, them (plural).
Theirdeterminer
Belonging to someone (one person, singular).
Theiradverb
misspelling of there
Theirpronoun
The possessive case of the personal pronoun they; as, their houses; their country.
