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Dolphins

Many people have experienced the joy of standing on a moving ship andwatching a group of dolphins swim alongside． Dolphins are not only playfulanimals but they are also highly intelligent． They are mammals that can befound in most of the world's oceans as well as in fresh water．

Dolphins can swim at speeds of up to 56 KPH and they can dive to depths of200 meters and stay underwater for 5-8 minutes without resurfacing for air．They are well-known for the unique clicking sound they use like sonar tolocate food as well as obstacles． Every dolphin has its distinctiveindividual whistling sound used for communication．

When dolphins sleep， they sleep in a semi-alert state by resting one sideof their brain at a time． They will help sick or injured dolphins as muchas they can， and they act as a team if there is danger．

It is because of these and other human-like qualities that people have aspecial feeling for dolphins．

海豚

許多人一定會(huì)有這樣開心的經(jīng)歷——站在航行的船上，看著一群海豚從旁邊游過。海豚不僅是一種有趣的動(dòng)物而且極其聰明。海豚是哺乳動(dòng)物，人們可以在世界上大多數(shù)的海洋和淡水中找到它。

海豚的游速可以達(dá)到每小時(shí)五十六公里，可以潛到兩百米深的地方，在水下待五到八分鐘而不浮出水面。海豚另一有名的特點(diǎn)是它們可以使用獨(dú)特的像聲波定位器一樣的敲擊聲來確定食物和障礙物的位置。每一頭海豚都有自己與眾不同的聲音，他們靠發(fā)出這種聲音互相交流。

當(dāng)海豚睡覺時(shí)，它們處于半驚醒狀態(tài)，每次只休息大腦的一半。它們會(huì)盡力幫助生病或受傷的海豚；在遇到危險(xiǎn)時(shí)，它們會(huì)相互協(xié)助。

正是因?yàn)檫@些及其他類似于人的特性，人們對(duì)海豚有著特殊的感情。