A key is a very useful tool. You can unlock doors with it. You can also lock things like jewelry so thieves can't take them away.
A key looks simple, but it is very important. It is a piece of metal with a special shape. It has a part that you can hold. If you want to use a key, you must have a lock. A lock has a hole where you put the key in. You can turn it left or right to lock or unlock a door, a car, a suitcase, a mailbox, a motorcycle, and more.
I can't imagine my life without keys. If there were no keys, no one would put locks on their houses, because nothing could open them, and thieves could come into our homes easily at any time.

鑰匙是一個很有用的東西。用它可以打開門，也可以把東西鎖起來，比如首飾，這樣小偷就拿不走。
鑰匙看起來很簡單，但其實很重要。它是一小塊特別形狀的金屬，上面有一個地方可以拿著。要用鑰匙，一定要有鎖。鎖上有一個洞，可以把鑰匙插進去，再往左或往右轉，就能把門、汽車、行李箱、信箱、摩托車等等鎖起來或打開。
我無法想像沒有鑰匙的生活。如果世界上沒有鑰匙，大家就不會裝鎖，因為根本沒有東西可以打開它。這樣一來，小偷就能隨時跑進我們家了。