Cách sử dụng
The expression "not a..." is used to express the opposite or absence of something. For example, if someone says "I'm not a doctor," it means that they are not a medical professional. This expression is commonly used in sentences to clarify what someone is not, and is often paired with a noun. You can use "not a..." in various settings, such as in a job interview, when introducing yourself, or in casual conversation. It's important to remember that this expression should only be used when you are certain of what you are not or do not have.