Herbert Weir Smyth, A Greek Grammar for Colleges

THE INTERROGATIVE PRONOUNS

[*] 1263. The interrogatives (pronouns and adverbs, 340, 346) are used in direct and in indirect questions. In indirect questions the indefinite relatives ὅστις, etc., are generally used instead of the interrogatives.

τί βούλεται ἡμῖν χρῆσθαι; for what purpose does he desire to employ us? X. A. 1.3.18, οὐκ οἶδα ὅ τι ἄν τις χρήσαιτο αὐτοῖς I do not know for what service any one could employ them 3. 1. 40, A. πηνίκ᾽ ἐστὶν ἄρα τῆς ἡμέρας; B. ὁπηνίκα; A. What's the time of day? B. (You ask), what time of day it is? Ar. Av. 1499.

N.—For peculiarities of Interrogative Sentences, see 2666, 2668.

[*] 1264. τί is used for τίνα as the predicate of a neuter plural subject when the general result is sought and the subject is considered as a unit: ταῦτα δὲ τί ἐστιν; but these things, what are they? Aes. 3.167. τίνα emphasizes the details: τίν᾽ οὖν ἐστι ταῦτα; D. 18.246.

[*] 1265. τίς asks a question concerning the class, τί concerning the nature of a thing: ““εἰπὲ τίς ἡ τέχνη” say of what sort the art is” P. G. 449a, τί σωφροσύνη, τί πολι_τικός; what is temperance, what is a statesman? X. M. 1.1.16, φθόνον δὲ σκοπῶν ὅ τι εἴη considering what envy is (quid sit invidia) X. M. 3.9.8.