一问三不知 一問三不知

    yīwènsānbùzhī

    1. Idiomliterally to reply "don't know" whatever the question (idiom); figuratively absolutely no idea of what's going on; complete ignorance

    关于这个项目的进展,他一问三不知。Guānyú zhège xiàngmù de jìnzhǎn, tā yīwènsānbùzhī.He knew nothing about the project's progress when questioned.