Questions: cxu, the ki- words and how to answer

One word at the front turns any statement into a yes/no question and nothing else moves: vi parolas Esperanton becomes ĉu vi parolas Esperanton? No inversion, no auxiliary do. Resist the English instinct: parolas vi Esperanton? reads as the statement with the verb stressed, not as a question. And ĉu never shares a direct question with a ki- word.

Ask ĉu vi ne venos? and jes means I AM coming, ne means I am not: Esperanto ignores the question's negative wrapping and answers the state of the world. English agrees, so anglophones coast, but Japanese and others run the opposite convention, which makes a one-syllable answer a coin toss in an international language. Answer with a clause instead. Two extra words, zero missed dinners. The all-purpose tag, meanwhile, is ĉu ne?, which never changes form.