The word thou is a second-person singular pronoun in English. It is now largely archaic, having been replaced in most contexts by the word you. It is used in parts of Northern England and in Scots. Thou is the nominative form; the oblique/objective form is thee, the possessive is thy (adjective) or thine and the reflexive is thyself. When thou is the grammatical subject of a finite verb in the indicative mood, the verb form typically ends in -(e)st, but in some cases just -t.
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