1. Dinosaurs were some of the biggest animals that have ever ____ (live) on the earth. living lives lived
2. Scientists have ____ (discover) a lot about these creatures. discover discovered discovering
3. They are always ____ (find) new information. finding findding found
4. Lately, scientists have been ____ (study) a new idea. studieing study studying
5. The idea is that dinosaurs might have ____ (have) warm blood - just like us! had have having
Unit 15