阅读下面的短文，按要求完成后面各小题：

　　All living things on the earth need other living things to live on．Nothing lives alone．Most animals must live in a group, and even a plant grows close together with others of the same kind．Sometimes one living thing tills(v．使平静another, one eats and the other is eaten．Each kind of life eats another kind of life in order to live, and together they form a food chain(n．链子)．Some food chains are simple, while others are not．But all food chains begin with the sun, and all food chains become broken up if one of the links(n．联系disappears．

　　All life needs sunlight to live on．But only plants can use sunlight directly．Plants are “factories”．They make food from sunlight, water and things in the soil and air．

　　Plants feed all other living things．Animals can only use the sun’s energy after it has been changed into food by plants．Some animals feed directly on plants, others eat smaller animals．Meat-eating animals are only eating plants indirectly．

What about human beings? We are members of many food chains．We eat wheat, rice, vegetables, fruits and so on．We also eat meat and drink milk．But men often break up the food chains．They make wild animals ill．They also make rivers, lakes and seas dirty．lakes these when rivers and are seas the eaten polluted in fish cannot them be．If men eat the fish, they will get strange diseases．

　　Each form of life is linked to all the others, Breaking the linked to all the others．Breaking the links puts all life in danger．

1．Which living things can use the sun’s energy directly?

2．What do plants make food from?

3．Who often break up the food chains?

4．请将划线的句子翻译中文．

5．将黑体部分组成一个完整的句子．