The cell-walls provide structural support to plant cells.

The cosmic walls of the universe are filled with mysteries.

The old house had dead walls covered in ivy.

The domain walls in the material separate different magnetic domains.

There were flies on the wall.

The fourth walls of the theater were painted a vibrant red.

The fourth-walls in this play are constantly being broken.

The hot walls of the sauna radiated warmth.

The ladder walls were covered in ivy.

The rat walls in the basement were infested with rodents.