Working outside the pit is dangerous.

Seigai is my best friend.

Mr. Sotozono is my best friend.

Insects have an exoskeleton, which protects their body.

This medicine is made outside of the body.

This sentence contains non-Jōyō kanji.

This sentence contains kanji not approved for regular use.

He started exercises to strengthen his abductors.

He is doing special exercises to strengthen his supinator.

He underwent surgery on his extraocular muscle.