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①自己对自己说话                                  ____

②一根头发上系着千军的重量，比喻情况万分危急。    ____

③本指集中众人的智慧，现专指一个人的紧身高度集中。____

    The giraffe is the tallest modern land animal. It can be over 5. 5 meters tall. Its neck alone may be 1. 9 meters long. Yet the giraffe has only seven bones in its neck, the same number as in the humans'. Even a small bird has many more bones in its neck than a tall giraffe. Each bone in a giraffe's neck is very long, while the bones in a human's neck are short. That makes the difference. A female giraffe gives birth to one baby at a time. The baby, called a calf, is about 1. 9 meters tall at birth. By the age of eight it is full-grown. The giraffe eats mostly leaves. Because it has a long neck, it can reach the high leaves on the trees.

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