He engaged in an extravehicular activity from the spaceship.

He is undergoing training for extravehicular activity.

He is studying about ancient military tactics.

This equation is linear.

This is a linear mathematical problem.

They waged war against the enemy country.

This pen is 15 centimeters long.

My thyroid gland is functioning normally.

Akane was wearing a madder-colored dress, which is the origin of her name.

This pig iron is a raw material for making high-quality steel.