Emperor penguins are the largest of all penguins—     1     average bird stands some 45 inches tall. 'These flightless animals live on the Antarctic ice and in the frigid surrounding water.

    2     (employ) physiological adaptations and cooperative behaviors, emperor penguins can deal with the incredibly difficult environment in Antarctic,    3     wind chills (寒冷) can reach -76°F. They escape wind and save     4     (warm) by gathering together. Once one penguin has warmed a bit it will move to tie perimeter (边缘) of the group so that others can enjoy protection     5     the icy environment.

Emperor penguins spend the long winter on the open ice — and even breed during this freezing season. In mid-May, females lay a single egg and then soon leave     6     behind. Throughout the winter, males keep the eggs warm while females make long journey to the open ocean     7     (feed) itself during the most unforgiving weather on the earth. When female penguins return to the breeding site with a belly full of food, with which they will feed the     8     (new) hatched chicks, the males     9    (suffer)bunger for four months and lost almost half their weight. Meanwhile, their duty done, male emperors make their way to the sea in search of food for themselves. In December, Antarctic summer, the pack ice begins to break up and open water     10     (appear) near the breeding site, just as young emperor penguins are ready to swim and fish on their own.