He is my best friend.

His actions show true mettle.

By valuing the daily routine of waking up and going to sleep, you can lead a healthy life.

Every day, he repeats the cycle of waking up and going to bed.

Looking at that person's behavior, I feel like they have some secret.

His mettle shows that he never gets discouraged even in difficult situations.

He expressed his opinion without any constraint.

He expressed his opinion without hesitation.

He is suffering from hunger.

There is a rare penguin in this zoo.