Do you know the difference between "backbone", "background", "backpack", and" backside"? All these words are based on the noun "back" but mean very different things. In this lesson, you will learn the meaning of ten words and expressions using "back". So don't back out. Watch the video, and you'll look back with satisfaction at the new vocabulary you've learned! Take a quiz at https://www.engvid.com/vocabulary-10-back-words/