He was standing on his two feet.

The two poles of the Earth are the North Pole and the South Pole.

This species of frog is hermaphroditic, able to change its sex as needed.

The United States has adopted a bicameral system.

We threw a party to celebrate the completion of the project.

The project has successfully completed.

I think this is really a good song.

This is an amphibious vehicle that can be driven on both land and water.

A frog is a type of amphibian.

He resigned because the chess game became difficult.