Allen and Greenough's New Latin Grammar for Schools and Colleges
J. B. Greenough, G. L. Kittredge, A. A. Howard, Benj. L. D'Ooge, Ed.

[*] a. The adverb -cumque (-cunque) (cf. quisque ) added to the relative makes an indefinite relative, which is declined like the simple word: as, quīcumque , quaecumque , quodcumque, whoever, whatever; cûiuscumque , etc.

[*] Note.--This suffix, with the same meaning, may be used with any relative: as, quāliscumque, of whatever sort; quandōcumque (also rarely quandōque ), whenever; ubicumque, wherever.

[*] b. In quisquis, whoever, both parts are declined, but the only forms in common use are quisquis , quidquid ( quicquid ) and quōquō .

[*] Note 1.--Rare forms are quemquem and quibusquibus; an ablative quīquī is sometimes found in early Latin; the ablative feminine quāquā is both late and rare. Cuicui occurs as a genitive in the phrase cuicui modī, of whatever kind. Other cases are cited, but have no authority. In early Latin quisquis is occasionally feminine.

[*] Note 2.-- Quisquis is usually substantive, except in the ablative quōquō , which is more commonly an adjective.

[*] c. The indefinite pronouns quīdam, a certain (one); quīvīs , quīlibet, any you please, are used both as substantives and as adjectives. The first part is declined like the relative quī , but the neuter has both quid- (substantive) and quod- (adjective):—

Quīdam changes m to n before d in the accusative singular ( quendam , M.; quandam , F.) and the genitive plural (quōrundam, M., N.; quārundam, F.).

[*] d. The indefinite pronouns quispiam, some, any, and quisquam, any at all, are used both as substantives and as adjectives. Quispiam has feminine quaepiam (adjective), neuter quidpiam (substantive) and quodpiam (adjective); the plural is very rare. Quisquam is both masculine and feminine; the neuter is quidquam ( quicquam ), substantive only; there is no plural. Ūllus , -a, -um, is commonly used as the adjective corresponding to quisquam .

[*] e. The indefinite pronoun aliquis (substantive), some one, aliquī (adjective), some, is declined like quis and quī , but aliqua is used instead of aliquae except in the nominative plural feminine:—

[*] Note.-- Aliquī is sometimes used substantively and aliquis as an adjective.

[*] f. The indefinite pronoun ecquis (substantive), whether any one, ecquī (adjective), whether any, is declined like aliquis , but has either ecquae or ecqua in the nominative singular feminine of the adjective form.

[*] Note.-- Ecquis ( ecquī ) has no genitive singular, and in the plural occurs in the nominative and accusative only.

[*] g. The enclitic particle -que added to the interrogative gives a universal: as, quisque, every one; uterque, each of two, or both. Quisque is declined

like the interrogative quis , quī :—substantive, quisque , quidque; adjective, quīque , quaeque , quodque .

In the compound ūnusquisque, every single one, both parts are declined (genitive unīuscûiusque ), and they are sometimes written separately and even separated by other words:—

1. “nē in ūnō quidem quōque ” (Lael. 92) , not even in a single one.

[*] h. The relative and interrogative have rarely a possessive adjective cûius (-a, -um), older quôius, whose; and a patrial cûiās (cûiāt-), of what country.

[*] i. Quantus, how great, quālis, of what sort, are derivative adjectives from the interrogative. They are either interrogative or relative, corresponding respectively to the demonstratives tantus , tālis (§ 152). Indefinite compounds are quantuscumque and quāliscumque (see § 151. a).