What are you doing, pipsqueak?

He has a stubborn personality and rarely changes his mind once he has made a decision.

His stubbornness sometimes causes problems.

This sushi has a taste of the highest quality.

The food at this restaurant is truly top-notch.

He lives by the moral code of the Three Bonds and Five Constant Virtues.

Scientists are developing a new type of fusion reactor.

Nuclear fusion is expected to be a future energy source.

He drew a pentagon on the blackboard.

He passed the exam.