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Snakes 蛇

Snakes are elongated 1, legless, carnivorous reptiles 2 that can be distinguished 3 from legless lizards 5 by their lack of eyelids 6 and external ears. Many species of snakes have skulls 7 with several more joints 8 than their lizard 4 ancestors, enabling them to swallow prey 9 much larger than their heads with their highly mobile jaws 10. To accommodate their narrow bodies, snakes' paired organs (such as kidneys) appear one in front of the other instead of side by side, and most have only one functional 11 lung., ,Living snakes are found on every continent except Antarctica, and on most smaller land masses; exceptions include some large islands, such as Ireland, Iceland, Greenland, the Hawaiian archipelago, and the islands of New Zealand, and many small islands of the Atlantic and central Pacific oceans. Additionally, sea snakes are widespread throughout the Indian and Pacific Oceans. More than 20 families are currently recognized. They range in size from the tiny, 10.4 cm (4.1 in)-long thread snake to the reticulated python of 6.95 meters (22.8 ft) in length. The fossil species Titanoboa cerrejonensis was 12.8 meters (42 ft) long. Snakes are thought to have evolved from either burrowing 12 or aquatic 13 lizards, perhaps during the Jurassic period., ,Venom 14 毒液,Most species are nonvenomous and those that have venom use it primarily to kill and subdue 15 prey rather than for self-defense. Some possess venom potent 16 enough to cause painful injury or death to humans. The colloquial 17 term "poisonous snake" is generally an incorrect label for snakes. A poison is inhaled 18 or ingested, whereas venom produced by snakes is injected into its victim via fangs 19. It is worthwhile noting that certain birds, mammals, and other snakes (such as kingsnakes) that prey on venomous snakes have developed resistance and even immunity 20 to certain venoms 21. Nonvenomous snakes either swallow prey alive or kill by constriction 22., ,Feeding and diet 饮食,All snakes are strictly 23 carnivorous, eating small animals including lizards, frogs, other snakes, small mammals, birds, eggs, fish, snails 24 or insects. Because snakes cannot bite or tear their food to pieces, they must swallow prey whole. The body size of a snake has a major influence on its eating habits. Smaller snakes eat smaller prey. Juvenile 25 pythons might start out feeding on lizards or mice and graduate to small deer or antelope 26 as an adult, for example. After eating, snakes become dormant 27 while the process of digestion 28 takes place.

根据上文判断对错
Snakes can be found everywhere in the world. 
a.  True
b.  False 
Some living snakes may be 12.8 meters (42 ft) long.
a.  True.
b.  False.
Not all species kill their preys 29 using venomous bites.
a.  True
b.  False 

答案
b b a