The wheel ____ a long time ago, around 3500 BCE, but no one knows who ____ it. It ____ for making pottery first. Later, people ____ it for transport. Carts were made, and heavy things were moved more easily. The idea of the wheel ____ in many places to many different people. Over time, civilizations ____ the design; for example, in the past, wheels were made with wood, which is heavy and slow, but now it's made with rubber. It is one of the most important inventions in history. Without it, many things could not be done. The world was changed by this simple idea.

Inventions

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