People must not leave bicycles in the hall. 5/20People must not leave bicycles in the hall. Bicycles must not be left in the hall. Bicycles in the hall must not being left. Bicycles in the hall must not left. Bicycles must been not left in the hall. Giải thíchĐáp án đúng: A Dịch: Xe đạp không được để ở trong hội trường.