Cách sử dụng
The expression "face up/down" is used to describe the position of an object. For example, if a book is "face up," it means the cover is facing upwards and the pages are visible. If the book is "face down," it means the cover is facing downwards and the pages are not visible. This expression can be used for any object that has a defined top and bottom, such as a phone, a card, or a picture frame.