21. We usually think of water as being a(n) ____________________, but it can also be a gas (water
vapor) or a solid (ice).
22. After years of ____________________, the scientist finally discovered a new species of fish.
23. It is important to protect beautiful animals such as leopards and cute animals such as pandas, but it is
also important to protect animals that do not seem so ____________________.
24. Many people think that all sharks are ____________________ creatures, but some species, such as
nurse sharks and whale sharks, are quite harmless to humans.
25. Elephants have a(n) ____________________ sense of smell when it comes to water. They can smell
water as far as 20 kilometers (12 miles) away.
26. Chameleons are an interesting species of lizard. They can change the color of their
____________________ to hide themselves or to send signals to other chameleons.
27. Tigers are almost invisible when they are standing in tall grass. The ____________________ of
stripes on their fur keeps them hidden from sight.
28. A tiger’s stripes allow it to ____________________ with its surroundings.