This document discusses vertebrate animals. It notes that vertebrates are classified based on their internal skeleton structure, which consists of bones. The skeleton provides strength and flexibility, allowing vertebrates to move using their head, torso and limbs in ways such as running, jumping, walking and flying. Common vertebrate groups mentioned include fish, birds, reptiles, mammals and amphibians. The document also lists onomatopoeic sounds made by some animals and verbs used to describe animal movements and actions.