key lock

例句：

1. 1.The key to solving the problem is to find the right solution.
   解决问题的关键是找到正确的解决方案。
2. 2.He locked the door securely with a key.
   他用钥匙锁上了门。
3. 3. The key to success lies in hard work and dedication.
   成功的秘密在于努力和奉献。