一位教授正在给一群留学生上礼仪课,由于学生都来自不同的国家,所以大家听得都很认真。“礼仪就是从细小的地方开始做起。比如说我刚才走进教室的时候,轻轻地敲了门。”教授告诉他的学生敲门是有讲究的:敲一声,代表试探;敲二声,代 A professor is giving etiquette classes to a group of international students. As students come from different countries, we all listen carefully. “The etiquette is to start from a small place, for example, I just entered the classroom, gently knocked on the door. ” Professor told his students knock on the door there is a stress: a knock on behalf of the temptation; knock Second sound, on behalf of