疑問代詞 INTERROGATIVE PRONOUN

quis quid [who? which? what?]

單數

陽類/陰類 中類
主格 quis quid
屬格 cuius cuius
與格 cui cui
賓格 quem quid
奪格 quo quo
 
複數 陽類 陰類 中類
主格 qui quae quae
屬格 quorum quarum quorum
與格 quibus quibus quibus
賓格 quos quas quae
奪格 quibus quibus quibus

quis librum tibi dedit? [Who gave you the book?]
cuius librum Caecilius tibi dedit? [Whose book did Caecilius give you?]
cui librum Grumio dedit? [To whom did Grumio gave the book?]
quid dedit? [What did he give?]
a quo praemium datum est? [By whom was the reward given?]

Interrogatives are sometimes modified by adding the prefix ec- or the suffix -nam.
ecquis? [is there anyone who?]
quisnam? [who, pray tell?]

quid? (n. acc.) can be used as an adverb to mean 'why?' [for what reason?].
Quid hic nunc stas? [Why are you standing here now?]