you mustn't be silly and drive without wearing a seat belt.什么意思

你不能这么傻,开车不系安全带mustn't 是禁止，不许意思，这里怎么讲的通呀mustn't + 行为动词 表式“禁止”mustn't + be，表示“一定不”注意区分：You mustn't stay at home。你不许呆在家里You mustn't be at home.你肯定不在家里。