Cats know that they have been sterilized. After sterilization, the cat's body will undergo great changes. The cat can feel it. When the cat is sterilized for a period of time, the changes in the body will trigger emotional changes, and the cat will become Grumpy, quiet, etc. Cats need careful care from their owners for a period of time after sterilization, to help clean wounds and pay attention to the cat's emotional changes.