Dutch questions fall into two types: yes/no questions (requiring ja/nee) and wh-questions (using a question word). Both use inversion: the finite verb comes first (or second after a question word), before the subject. Yes/no question: “Woon jij in Amsterdam?” (Do you live in Amsterdam?) — verb before subject. Wh-question: “Waar woon jij?” (Where do you live?) — question word in first position, verb in second, subject third.
Dutch question words: wie (who), wat (what), waar (where), wanneer (when), waarom (why), hoe (how), hoeveel (how much/many), welk/welke (which). Wie is for people; wat for things. Hoe combines with adjectives: hoe groot (how big), hoe oud (how old), hoe ver (how far). Questions about things following a preposition use waar- + preposition: “Waar denk je aan?” (What are you thinking about?).
The jij/je inversion rule also affects questions: when jij or je follows the verb (as in all yes/no and wh-questions), the -t disappears from the verb: “Kom jij ook?” not “Komt jij ook?” This applies only to jij/je — not to u, hij, zij or any other pronoun. Tag questions in Dutch typically use toch? (right?/isn’t it?) or hè? (informal): “Dat is goed, toch?” (That’s good, right?).