The water in this area has a high arsenic content.

The cortex of his brain is highly developed.

Ohishiba is one of the common weeds seen in Japanese gardens and fields.

This tree is very hard.

He chose that method against his will.

He is a person with a strong heart.

He finished the job in slightly more than an hour.

Tsuyoshi is my best friend.

He is a very strong person.

His strength comes from his mental power.