一个铝罐的质量约10克，如果不踩扁它，数量多的时候就会占很大的空间。
An aluminum can has a mass of about 10 grams. If you don’t flatten it, it will take up a lot of space.
步骤一： 先踩铝罐的中间部分（如上图）
Step 1: First step on the middle part of the aluminum can (pictured above)
步骤二：踩右边部分（如上图）
Step 2: Step on the right part (picture above)
步骤三：踩左边部分（如上图）
Step 3: Step on the left part (picture above)
备注：铝罐必须是干净、不潮湿，最好先清水一遍，避免引来蚂蚁等昆虫。
Remarks: Aluminum cans must be clean and dry. It is best to clear the water first to avoid attracting insects such as ants.
