In English, you can use "how" in different ways, like "how (to do something)" and "how (tall/big/small)", but that's not the case in Chinese! The first how refers to the manner of doing something, which you've already learned in past lessons - 怎么 (zěn me). Today, you'll learn how to say the second "how" in Chinese, which refers to the degree or extent of something! You'll learn sentences like "How old are you?", "I'm __20/30__ years old this year.", "How tall are you?", and more!