题目内容：

阅读下列短文，回答问题（不得超过7个词）

People kill. Animals kill. Animals and people kill for food, or they kill their enemies. People and animals can move around and find something to kill. They can run away from an enemy. They can sometimes kill it if it is necessary.

Many kinds of animals eat plants. The plants cannot run away from their enemies. Some plants make poison. If an animal eats part of the plant, it will get sick or die. Animals learn to stay away from these plants. There are many kinds of plants that make poison. Most of them grow in the desert or in the tropics.

Today farmers use many kinds of poison on their farms. Most of these poisons come from petroleum(石油), but petroleum is expensive. Scientists collect poisonous plants and study them. Maybe farmers can use cheap poison from plants instead of expensive poison from petroleum in the near future.

1.Why do animals and people kill? ______________________________

2.What can people and animals do when meeting an enemy?_______________

3.How will the animal be if it eats some of the poisonous plant?____________

4.Where do most plants that make poison grow? ___________________

5.What may farmers use on their farmers in the future?  _______________