When you travel in South America, you’d better pay attention to the following three kinds

When you travel in South America, you’d better pay attention to the following three kinds of dangerous South American animals.
Piranhas（水虎鱼）
Although only a small number of piranhas are considered to be dangerous to humans, the red-bellied piranha is definitely one of those. Evidence has shown that a large group of piranhas can absolutely eat a herd of large animals crossing the river, leaving only bones. This fish lives in the freshwater streams of South America, and they can smell the blood from far away and launch attacks swiftly. It is said that they are only dangerous to humans if the water volumes are less and lower.
Anacondas（水蟒）
This South American monster of a creature often appears in the films or your nightmares！They have weighed over 230 kilograms. It is often considered to be the biggest snake in the world. You certainly don’t want to get caught alone with this snake due to its method of attacking and killing its victim. It is indeed a remarkably different brand of snake type as it regularly coils（缠绕）around all over its target, increasing the pressure until eventually its victim dies. Its jaws are powered by large muscles that produce enough power for its over 100 sharp teeth to pass through the thick skin of an crocodile. They don’t have poison. Sometimes they prefer to camouflage themselves so they look like their surroundings and swiftly draw back when humans are near.
Golden Poisonous Frogs
The golden poison frog might be the most-deadly of the South American animal, which is protected by means of poison. This very small frog, less than 55 mm in length, packs enough punch（效力）to take down a pair of African bull elephants. This apparently harmless frog has always been known to have killed people who have touched it directly. It’s also been noted that chicken and dogs have died by contacting things on which a golden poison frog had wandered! In intense colors, they normally look attractive to their targets.
【小题1】What can we learn about piranhas from the passage?A．Piranhas are the most dangerous animals.B．Piranhas like to live in the deep seabed.C．Piranhas may attack human beings when the water level is low.D．Piranhas only attack human beings when they cross the river in groups.【小题2】How does an anaconda kill its victim according to the passage?A．It often uses its poison to kill its victim.B．It often uses its strength to kill its victim.C．It kills its victim mainly using its powerful teeth.D．It kills its victim with the help of other snakes.【小题3】The underlined word “camouflage” in Paragraph 3 means “ ”.A．hide itself by appearing like the surroundingsB．terrify and capture the enemy by making much noiseC．move around to search for delicious foodD．give off harmful gas to kill the targets【小题4】Chicken and dogs are mentioned in Paragraph 4 to show that .A．no animals can survive the poison of the golden poison frogB．they like to wander along the path of the golden poison frogC．the golden poison frog likes eating them most D．the poison of the golden poison frog is deadlyC

(答案→)C 解析：本文描述了南美三种危险的动物：水虎鱼，水蟒和金毒蛙。【小题1】从第二段最后一句It is said that they are only dangerous to humans if the water volumes are less and lower可得知正确答案为C。解题时也可以根据选项结构及内容先答案应该是在CD两项中确定，再进一步找信息句排除选项D。【小题2】从第三段.... it regularly coils（缠绕）around all over its target, increasing the pressure until eventually its victim dies可得知水蟒主要是通过它的力气将目标物缠绕致死，故选择B。【小题3】从第三段so they look like their surroundings可以得知答案C，即乔装自己使它们看起来像周围的环境从而躲避自己。【小题4】文章最后一段主题句是The golden poison frog might be the most-deadly of the South American animal, which is protected by means of poison。然后通过举例子人，鸡，狗等动物论证支撑这一观点，故选D

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