Completar frases Fill in the gaps activityVersión en línea Based on the reading complete the following sentences por Karen Quintero 1 land wings dry water spinal column scales fly frog feathers eggs Vertebrates are animals that have a backbone or , also called vertebrae . They are classified into 4 categories : Mammals : are warm - blooded animals that nurse their young with milk and have fur . For example , the lion . Reptiles : are cold - blooded animals which lay . Their skin is covered with hard and dry . For example , the crocodile . Birds : are animals that have , , and lay eggs . Many , but not all , birds can . For example , the eagle . Amphibians : are cold - blooded animals . They start out their lives living in the with gills . Later they develop lungs and can move to . For example , the .
Crear