Shunji is my best friend.

He is outstanding in his field.

Toshin came up with a sagacious way to solve the problem.

We wrote essays for peer grading.

He works at the switchboard.

We exchanged our old books for new ones through barter.

We write in the exchange diary every day.

I exchanged my old smartphone for a new one.

Let's exchange keys tomorrow.

He was born as an illegitimate child and experienced many difficulties.