1We know that many animals do not stay in one place. Birds, fish and other animals move from one place to another at a certain time. They move for different reasons most of them move to find food more easily, but others move to get away from places that are too crowded. When cold weather comes, many birds move to warmer places to find food. Some fishes give birth in warm water and move to cold water to feed. The most famous migration（迁移）is probably the migration of the fish, which is called “salmon”（大马哈鱼）. This fish is born in fresh water but it travels many miles to salt water. There it spends its life. When it is old, it returns to its birthplace in fresh water. Then it gives birth and dies there. In northern Europe, there is a kind of mice. They leave their mountain homes when they become too crowded. They move down to the low land. Sometimes they move all the way to the seaside, and many of them are killed when they fall into the sea. Recently, scientists have studied the migration of a kind of lobsters（龙虾）. Every year, when the season of bad weather arrives, the lobsters get into a long line and start to walk across the floor of the ocean. Nobody knows why they do this, and nobody knows where they go. So, sometimes we know why humans and animals move from one place to another, but at other times we dont. Maybe living things just like to travel. 1. Most animals move from one place to another at a certain time to _ . A. give birth B. enjoy warmer weatherC. find food more easily D. find beautiful places2. The mice in northern Europe move when _ . A. they give birth B. the weather is badC. the place gets too crowded D. they havent enough food3. The lobsters move _ . A. to the fresh water B. to the sea floorC. to find more food D. at a certain time4. What is the main idea of the passage?A. Animals move in order to find food more easily. B. The migration of the fish called “salmon” is the most famous migration. C. Living things move from one place to another because they like to travel. D. Sometimes we know why and how living things move from one place to another but we dont sometimes. 2Certain animals and plants develop characteristics that help them deal with their environment better than others of their kind. This natural biological process is called adaptation. Among the superior characteristics developed through adaptation are those that may help in getting food or shelter, in providing protection, and in producing and protecting the young. That results in the gradual development of more and more organisms（small living things）that are better fitted to their environments. Each living thing is adapted to its way of life in a general way, but each is adapted especially to its own distinct class (kind ) . A plant, for example, depends upon its roots to fix itself firmly and to absorb water and inorganic chemicals (无机化学物). It depends upon its green leaves for using the suns energy to make food from inorganic chemicals. These are general adaptations, common to most plants. In addition, there are special adaptations that only certain kinds of plants have. Many animals have adaptations that help them escape from their enemies. Some insects are hidden by their body color or shape, and many look like a leaf or a little branch. The coats of deer are colored to mix with the surroundings. Many animals have the ability to remain completely still when an enemy is near. Organisms have a great variety of ways of adapting. They may adapt in their structure, function, and genetics; in their development and production of the young; and in other respects. An organism may create its won environment, as do warm-blooded mammals, which have the ability to adjust body heat exactly to maintain their ideal temperature despite changing weather. Usually adaptations are an advantage, but sometimes an organism is so well adapted to a particular environment that, if conditions change, it finds it difficult or impossible to readapt to the new conditions. 1. Some plants and animals develop superior characteristics so that they may . A. help others of their kind get food, shelter and other things needed B. survive even in extremely severe conditions C. become better adapted to the environments than others of their kind D. result in the evolution and production of more intelligent organisms 2. In the first paragraph, the word environments could best be replaced by . A. contexts B. surroundings C. neighbors D. enemies 3. It can be inferred from this passage that the feathers of a bird are colored . A. to frightened its enemies. B. to attract its enemies C. to adjust its body heat