Cách sử dụng
The expression "once a…, always a…" means that once someone has a certain characteristic or behavior, they will usually keep that characteristic or behavior for a long time or forever. For example, if someone says "once a liar, always a liar," it means that if someone has a habit of lying, they will likely continue to lie in the future. This expression can be used in many situations, from talking about someone's personality to someone's behavior at work or school.