We sometimes call the lion "the king of the forest" , because it is stronger and more dangerous than other animals. It can 1 faster than many animals and hunt the best. It is the highest animal in the 2 food chain.
In the sea, the shark is one of the animals at the top of the food chain. It can swim faster than 3 other sea animals, and it can use its big teeth to eat them.
What is at the top of the world's food chain？People are! We are not the biggest or fastest, but we are the 4.We could not run faster than cheetahs (猎豹), so we 5 cars and now we can move the fastest. We could not fight better than lions, so we invented guns. Now we can hunt the best.
People's inventions are clever, but they can be 6 ， too. For example, people built 7 ， and now they make the air and rivers dirty. This can make terrible changes. Dirty rivers kill fish.8 bears cannot eat the fish. If we kill one part of the food chain, other parts will also die. Remember that we are a part of the food chain, 9 we are in danger, too! If we protect animals, we are protecting 10! We could and we should do something for the world!
