Goold Brown,
The Grammar of English Grammars
(1882)
“ The Indicative mood is that form of the verb, which simply indicates or declares a thing: as, I write; you know: or asks a question; as, "Do you know?"--"Know ye not?" The Potential mood is that form of the verb which expres ses the power, liberty, possibility, or necessity, of the being, action, or passion: as, "I can walk; he may ride; we must go." The Subjunctive mood is that form of the verb, which represents the being, action, or passion, as conditional, doubtful, and contingent: as, "If thou go, see that thou offend not."--"See thou do it not."--Rev., xix, 10. ”
