问题
选择题
下列哪些特征有利于鱼克服在水中游泳时的阻力？（ ）
A．身体呈梭形或流线型
B．体表覆盖着鳞片
C．体表可以分泌黏液
D．以上三项都对
答案
鱼的头部和尾部较尖，躯干部宽大，身体侧扁，为梭形，体表覆盖着大量的鳞片，能分泌粘液，比较粘滑，可以减少在水中的阻力，适于在水中生活．
故选：D
搜题请搜索小程序“爱下问搜题”
下列哪些特征有利于鱼克服在水中游泳时的阻力？（ ）
A．身体呈梭形或流线型
B．体表覆盖着鳞片
C．体表可以分泌黏液
D．以上三项都对
鱼的头部和尾部较尖，躯干部宽大，身体侧扁，为梭形，体表覆盖着大量的鳞片，能分泌粘液，比较粘滑，可以减少在水中的阻力，适于在水中生活．
故选：D
Wang Hai has just 1 his middle school but he couldn’t go to high school because there wasn’t 2 for it. His father wanted him to help with his business and let his little brother go to school. Soon Project Hope 3 it. They gave his father some money and asked his father to let him 4 to school again. He thanked the uncles and aunts in Project Hope a lot. Now he has been in school for a year. His teacher said he was a good student and 5 very hard.
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