难道【nándào】

难道 starts a question that expects no answer. The speaker already believes the opposite of what the question says, and the question shows surprise or impatience. The sentence usually ends in 吗.

A negative 难道 question means yes, and a positive one means no. 难道你不知道吗 says you know; 难道你忘了吗 says you can't have forgotten.

难道 can go before the subject or after it.

难道…不成 is a more literary ending with the same force.

Not a neutral question

难道 carries an edge: the speaker thinks the listener should already know, or has done something odd. Asking a stranger a real question with it sounds rude.

• × 难道你是学生吗？ (to someone you've just met) → 你是学生吗？