1. Dinosaur Fossils By: Dr. Alvin Granowsky

2. fossils Hardened remains of an animal or plant that lived long ago.
The fossil of the leaf imprint was found in sandstone.

3. hardened
Became solid
After the lava hardened we were able to walk on top of it.

4. scientists People who study things in nature.
Paleontologists are scientists who study fossils.

5. difficult Something that is not easy to do.
It would be difficult to play the piano backwards.

6. extinct No longer living.
Many animals have become extinct, there are none of them left in the world.