Mr. Zhai is my best friend.

He has a weary character.

My high school has very strict rules.

He was arrested for obstruction of public duties.

He is a genius, but even experts sometimes make mistakes. He also makes mistakes sometimes.

Biotechnology is a science that understands the mechanisms of life and utilizes them.

This road is a dead end, so we have to find another way.

The Commonwealth of Independent States is an intergovernmental organization formed by part of the former Soviet Union.

When you cross the International Date Line, the date changes by one day.

The Mitsukuri's lantern shark is a rare fish that lives in the deep sea.