1. If the stir-fried vegetables are too spicy, you can add vinegar to relieve the spicy taste, because vinegar contains acetic acid, which can neutralize some capsaicin in peppers, thus removing some spicy taste.

2. Adding vinegar when cooking is better than dipping vinegar when eating, because capsaicin will lose more when heated in acidic environment. In addition, for the soup that is too greasy, in addition to skimming the oil on the surface, adding vinegar can also reduce the greasy feeling.