That's rude. Halfway through the class, I couldn't help being hungry. On the one hand, it makes other students feel uncomfortable in class, on the other hand, it affects teachers' interest in teaching, making the overall classroom efficiency low; At the same time, for him personally, not only the first few minutes of each class are lost, but also because of the tolerance of his classmates, he becomes numb to this kind of behavior in the long run, leading to the continuous strengthening of procrastination and the formation of habits. Too late to eat, just rushed into the classroom at the last minute and listened to the class while eating; People who do this may find it understandable. After all, they still occupy the moral high ground in choosing whether to be late or not, so they think people around them should be tolerant.