The phrase "are on the back of" implies that something is positioned or located behind an object. To express the opposite meaning, we can use antonyms such as "in front of," "on top of," or "above." These words indicate that something is placed or located in a way that is opposite to being on the back. For instance, if we say that the label is on the back of the bottle, the antonym would be that the label is in front of the bottle or on top of it. Knowing antonyms helps to expand our vocabulary and communicate more effectively by providing alternative words to express opposing concepts.