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What amazing animals snakes are! Some lay eggs, others give birth to young（生小蛇）. Some live on the ground, some in trees. Snakes that live only in trees are called arboreal（栖息在树上的）. Some live both on the ground and in the trees. Some even live in water. They slide around with great speed and with no legs.
Snakes seem“charmed”（有魔力的） by a snake charmer’s flute（笛子）, but they are really deaf. They can swallow（吞） something twice as big around as they are.
What do they feel like? Smooth, cool plastic. They do not feel“slimy”（黏滑的） as many people think. Worms may feel slimy, but not snakes.
Since there are hundreds of kinds of snakes, we can’t talk about all of them. But we can talk about how they are alike.
How do they move so fast with no legs？The scales（鳞） on a snake’s body are also very flexible（灵活的）on its underside. When it bends its body the scales underneath push against whatever is under the snake. This moves it away from the direction of the push. When it gets many scales pushing at the same time by bending its body in several places at once—off it goes, sometimes with surprising speed.
How can they be so wiggly（蜿蜒的）？ A snake’s skeleton（骨骼） and body parts are very flexible—something like a rubber hose（软管） with bones. Its backbone can have as many as 300 vertebrae（椎骨）.（A human’s has only thirty-three or thirty-four.）The connecting tissues（结缔组织）between a snake’s vertebrae are loose and like rubber, much more so than in any other living animal. Because of this bending, twisting ability a snake can bend its body in almost any direction at almost any point.
Do snakes really lay eggs？Some do, and some don’t. In either case, live-born（直接生的）or hatched（孵化的），the babies are on their own from the minute they are born（生来就独立）. Some poisonous snakes are able to produce poison in their very first bite. Their mother wants nothing to do with them, except maybe to eat them.
How big do snake get？ There are hundreds of kinds that are as long as 3 meters. There are just as many from 0.3 to 2.4 meters long. Next are snakes less than 0.3 meters long. Finally, the tiny blind snakes that live under the ground can be mistaken for worms if one does not look at them closely. The champion for length in the snake world are the South American anaconda（蟒蛇）and the python（巨蟒）of Asia. Both have been known to reach 9 meters in length. That’s almost as long as two station wagons（旅行客车）.
When do they shed their skins（脱皮）？Snakes shed their skins when they outgrow them（长得快）. This happen continually, because snakes keep growing throughout their lives, although more slowly as they get older. The skins are discarded（放弃） at regular intervals（间隔） of one or three months, according to the variety of snake. During this process, which is known as sloughing（蜕皮）, the old skin is turned back on itself, beginning at the lips and gradually revealing（显露） the new skin underneath. When sloughing has ended, the old skin will have been turned completely inside out and left in one piece.
How do they kill their victims（猎物）？ Snakes have several ways of getting a meal. The small insects snakes just grab and swallow. Some larger snakes are constrictors（紧绕猎物使其窒息而死的蛇）, and some are not. The constrictors grab their victims with a lightning-quick dart of the head. Then they quickly wrap their bodies around it like a coil, and squeeze（紧勒）. This keeps the animal from breathing and helps to stop its heart action. Most of the time animals are swallowed head first.
Nonconstrictors grab their meal and pin it to the ground with their bodies while the swallowing begins. Meals are swallowed alive.
Poisonous snakes snatch（抓住） their meal and inject（射入） the poison through to special hollow teeth. They wait until the animal stops fighting as the poison starts to work. Then they begin their meal.
Snakes seem“charmed”（有魔力的） by a snake charmer’s flute（笛子）, but they are really deaf. They can swallow（吞） something twice as big around as they are.
What do they feel like? Smooth, cool plastic. They do not feel“slimy”（黏滑的） as many people think. Worms may feel slimy, but not snakes.
Since there are hundreds of kinds of snakes, we can’t talk about all of them. But we can talk about how they are alike.
How do they move so fast with no legs？The scales（鳞） on a snake’s body are also very flexible（灵活的）on its underside. When it bends its body the scales underneath push against whatever is under the snake. This moves it away from the direction of the push. When it gets many scales pushing at the same time by bending its body in several places at once—off it goes, sometimes with surprising speed.
How can they be so wiggly（蜿蜒的）？ A snake’s skeleton（骨骼） and body parts are very flexible—something like a rubber hose（软管） with bones. Its backbone can have as many as 300 vertebrae（椎骨）.（A human’s has only thirty-three or thirty-four.）The connecting tissues（结缔组织）between a snake’s vertebrae are loose and like rubber, much more so than in any other living animal. Because of this bending, twisting ability a snake can bend its body in almost any direction at almost any point.
Do snakes really lay eggs？Some do, and some don’t. In either case, live-born（直接生的）or hatched（孵化的），the babies are on their own from the minute they are born（生来就独立）. Some poisonous snakes are able to produce poison in their very first bite. Their mother wants nothing to do with them, except maybe to eat them.
How big do snake get？ There are hundreds of kinds that are as long as 3 meters. There are just as many from 0.3 to 2.4 meters long. Next are snakes less than 0.3 meters long. Finally, the tiny blind snakes that live under the ground can be mistaken for worms if one does not look at them closely. The champion for length in the snake world are the South American anaconda（蟒蛇）and the python（巨蟒）of Asia. Both have been known to reach 9 meters in length. That’s almost as long as two station wagons（旅行客车）.
When do they shed their skins（脱皮）？Snakes shed their skins when they outgrow them（长得快）. This happen continually, because snakes keep growing throughout their lives, although more slowly as they get older. The skins are discarded（放弃） at regular intervals（间隔） of one or three months, according to the variety of snake. During this process, which is known as sloughing（蜕皮）, the old skin is turned back on itself, beginning at the lips and gradually revealing（显露） the new skin underneath. When sloughing has ended, the old skin will have been turned completely inside out and left in one piece.
How do they kill their victims（猎物）？ Snakes have several ways of getting a meal. The small insects snakes just grab and swallow. Some larger snakes are constrictors（紧绕猎物使其窒息而死的蛇）, and some are not. The constrictors grab their victims with a lightning-quick dart of the head. Then they quickly wrap their bodies around it like a coil, and squeeze（紧勒）. This keeps the animal from breathing and helps to stop its heart action. Most of the time animals are swallowed head first.
Nonconstrictors grab their meal and pin it to the ground with their bodies while the swallowing begins. Meals are swallowed alive.
Poisonous snakes snatch（抓住） their meal and inject（射入） the poison through to special hollow teeth. They wait until the animal stops fighting as the poison starts to work. Then they begin their meal.