I was surprised by his stupidity.

The aardvark is a rare animal that lives in Africa.

This project is still in its infancy.

He has experienced a life of hardship and wandering.

He returned from a long journey and was exhausted and wandering aimlessly.

He was standing at the top of the mountain.

Kawachi is my best friend.

His actions led to the problem.

That accident was caused by his lack of attention.

The mesosphere is a part of the Earth's atmosphere, located between the stratosphere and the thermosphere.