The Greek interrogative pronoun τίς is the New Testament's all-purpose question word, covering persons ('who?'), things ('what?'), and reasons ('why?'). Its flexibility comes from Greek's case system — the same root word shifts meaning with prepositions and grammatical context. When Jesus asks τί μεριμνᾶτε ('why are you anxious?', Matt 6:28), the accusative neuter functions causally. Spanish carefully distinguishes 'quién' (who) from 'qué' (what) and 'por qué' (why), revealing three distinct semantic slots that Greek bundles into one versatile pronoun. A handful of occurrences shade into indefinite meaning — 'someone' or 'anything' — blurring the line between question and assertion.