He is a complete stranger to me.

They were showing each other their pictures.

She bought new boyshorts.

He was caught by the secret police.

He believes that there is a secret base on that island.

He is rumored to be a member of a secret society.

He built a fish pond in his backyard.

He encrypted the message using a public key.

Let's exchange keys tomorrow.

He is good at playing the black keys.