Zenodotos invented the terms singular, plural, and dual. The scholars of Alexandria and of the rival academy of Pergamos were the first to distinguish language into parts of speech, and to give technical terms to the various functions of words.
The first Greek grammar was by Dionysios Thrax, and it is still extant. He was a pupil of Aristarchos. Julius Cæsar was the inventor of the term ablative case.
English grammar is the most philosophical ever devised; and if the first and third personal pronouns, the
relative pronoun, the 3rd person singular of the present indicative of verbs, and the verb “to be” could be reformed, it would be as near perfection as possible.
It was Kaiser Sigismund who stumbled into a wrong gender, and when told of it replied, “Ego sum Imperator Romanorum, ct supra grammaticam”' (1520, 1548-1572).
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894