因为 from HSK Level 2 Vocabulary List

The Chinese word 因为 (yīnwèi) is a conjunction that means "because" or "due to". It is composed of two characters: 因 (yīn), which means "cause" or "reason", and 为 (wèi), which means "to do" or "to be". Together, these characters mean "to do something because of a reason".The word 因为 is first recorded in the Han dynasty (206 BCE - 220 CE). It is thought to have originated from the earlier word 以故 (yǐgù), which also means "because" or "due to". The character 故 (gù) in 以故 means "reason" or "cause", and the character 以 (yǐ) is a preposition that means "because of" or "due to".The word 因为 is used in both spoken and written Chinese. It is a common conjunction that is used to connect two clauses or sentences. For example, the sentence "我迟到了，因为我睡过头了" (wǒ chídàole, yīnwèi wǒ shuì guòtóule) means "I was late because I overslept".The word 因为 can also be used as a noun. In this case, it means "the reason why" or "the cause of". For example, the sentence "迟到的原因是因为我睡过头了" (chídàode yuányīn shì yīnwèi wǒ shuì guòtóule) means "The reason why I was late is because I overslept".The word 因为 is a versatile word that can be used in a variety of ways. It is an important word to know for HSK learners, as it is used frequently in both spoken and written Chinese.