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The biggest animal on land and sea is the whale. It seems to be a large fish. In fact, it is a mammal. A fish can get oxygen from water but a mammal must take in oxygen from the air.      You are a mammal. You might be able to inhale enough air to stay under the water about half a minute. Then you must come up and exhale. But whales can stay under the water for fifteen minutes. Then they must come up and exhale. What a huge breath! The huge breath of a whale makes a big spout. It looks like a cloud. Whales are not the only mammals in the ocean.
1. What is the biggest animal on land and sea?
A. The elephant               B. The eagle                C. The butterfly        D. The whale
2. What kind of animal is the whale?   A. It is a mammal                              B. It is a fish             
   C. It is a bird                                      D. It is a worm3. Where must a mammal take in oxygen from?   A. In the water                      B. In the air                 
In the water and the air      D. In the oceans.
4. How long can whales stay under the water?  A. For half a minute              B. For fifty minutes    
  C. For fifteen minutes             D. For fifty-five minutes.5. What does the huge breath of a whale look like?  A. A cloud                 B. A fish               C. A mammal                  D. A big spout.