Cách sử dụng
A knapsack is like a bag that you wear on your back. It's usually made of cloth or leather, and people use it to carry things around with them when they're walking or hiking. You might also hear the word "backpack" used instead of "knapsack." So if you're going on a trip or need to carry some things with you while you walk, you could use a knapsack or backpack to hold your stuff.