You must never show this secret key to anyone else.

He encrypted the message using a public key.

Let's exchange keys tomorrow.

The police are doing their best to search for the fugitive.

He likes to take a walk in the park at dusk.

We should always remember the power of Kannon in difficult times.

This ancient proverb, 'know the other side and yourself, and you will not be in danger in a hundred battles', teaches us the importance of understanding ourselves and others.