ART n.
The second person singular, indicative mode, present tense, of the substantive verb Be; but formed after the analogy of the plural are, with the ending -t, as in thou shalt, wilt, orig. an ending of the second person sing. pret. Cf. Be. Now used only in solemn or poetical style.
AUXILIARY n.
A verb which helps to form the voices, modes, and tenses of other verbs; -- called, also, an auxiliary verb; as, have, be, may, can, do, must, shall, and will, in English; être and avoir, in French; avere and essere, in Italian; estar and haber, in Spanish.