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Every year animals all around the world take part in some wonderful journeys．Here are the stories of two amazing animal travelers．
Humpback whales （ 座 头 鲸 ） prefer a slow journey．The humpbacks，
which travel over 10，000kilometers on their journey from Alaska to Hawaii，swim at a relaxing speed of about 1.6kilometers an hour．Although they don't swim fast，humpback whales travel farther than any other kinds of whale．
Every August a fantastic sight can be seen in the skies above Ontario and Montreal﹣millions of amazing Monarch butterflies （ 帝 王 蝶） beginning their 4，000﹣kilometer journey from Canada to Central Mexico．In fact，the journey，which takes about 3months，is longer than the average （ 平 均 的 ） life of the butterfly．Finally many of the butterflies reaching their final place are the great grandchildren or even the great great grandchildren of the butterflies who began the journey in Mexico the year before．
Humpback whales swim at a speed of an hour from Alaska to ．They travel slowly but among all whales．Monarch butterflies spend flying from Canada to Central Mexico．It lasts longer than their average life．The ones which arrive at the final place are or even the great great grandchildren．
The passage is mainly about．
