All living things on the earth need other living things to live with. Nothing lives alone. Sometimes one living thing kills another to live, so they form a food chain.
Plants make food from sunlight, water, air and so on while some animals on(以……为食) plants directly. For example, locusts(蝗虫) are small insects. Millions and millions of locusts in a group can eat anything that is green, including a lot of food that people need. In India, locusts have ever destroyed(破坏) many fields of crops. However, locusts can be food for birds, chickens, ducks or other living things, even humans.
Humans are at the top of the food chain, they eat not only locusts, but also birds, chickens, ducks or many other plants and animals. They are members of many food chains, but they often break up the food chains.
Each form of life is linked(和……有联系) to all the others. Breaking the links puts all lives in danger. Humans should share the world with other living things in peace.
【小题1】No living things can live alone.【小题2】Some animals eat plants directly to live.
【小题3】Locusts don’t eat food that people need.
【小题4】Humans hardly ever break up the food chains.
【小题5】It’s dangerous for humans to break up the food chains.
