Cách sử dụng
The expression "how, why, where, who, etc. on earth" is typically used to express surprise, confusion, or frustration about something. It's essentially a way of emphasizing a question or statement. For example, if someone asks you a complicated question that you have no idea how to answer, you might respond with "How on earth am I supposed to know that?!"This expression can be used in many different situations, such as when you're surprised about something someone said or did ("Why on earth would you do that?"), when you're confused about a particular instruction or task ("Where on earth do I start?"), or when you're frustrated about a difficult problem you're trying to solve ("Who on earth thought this was a good idea?")Overall, the expression is a way to express strong emotions and draw attention to a particular question or statement. It's commonly used in casual conversation, so it's important for English learners to understand it and be able to use it appropriately.