ESL, pažengęs lygis

Real Life: Animals & Habitats (2)

In cold climates, some animals ........., falling into a long, deep sleep during the cold winter months. They usually find warm, dry places to sleep in for several months at a time. Bears and frogs do this in cold climates every year.
During the cold winter months, many animals ......... from colder areas to warmer regions. They often travel long distances so that they can find food easily and protect themselves from harsh winter conditions. In the spring, they travel back to their original locations. Some birds do this every year.
However, some animals grow thicker coats of fur just before the winter. This process is called ........., and this helps them survive in harsh conditions.
In addition to thicker winter coats, some animals ......... themselves with a different color. For example, the Arctic Fox grows a thick white coat in the winter in order to blend into its surroundings.
Animals that are hunted and killed by other animals are known as ..........
Animals that hunt and kill other animals are called ..........
......... are animals that are warm-blooded, grow hair or fur, and produce milk for their babies.
Animals are classified in different ways. For example, some animals have backbones or spinal columns, and they are called ..........
Some animals don't have backbones or spinal columns, and they are classified as ..........
Another animal category is the .......... These are invertebrates like bees or bugs that have no backbone but six legs.