THEY, pron. plu. objective case, them.
1. The men, the women, the animals, the things. It is never used adjectively, but always as a pronoun referring to persons, or as a substitute referring to things.
They and their fathers have transgressed against me. Ezekiel 2
They of Italy salute you. Hebrews 13
Blessed are they who hunger and thirst after righteousness. Matthew 5
2. It is used indefinitely, as our ancestors used man, and as the French use on. They say, on dit, that is, it is said by persons, indefinitely.