The Mule

（单词翻译:单击）

    A mule¹ that had grown fat and wanton on too great an allowance of corn，was one day jumping and kicking about，and at length，cock-ing up her tail，exclaimed，“My dam was a racer，and I am quite as good as ever she was．”But being soon exhausted² with her galloping³ and frisking，she remembered all at once that her sire was but an ass⁴．Every truth has two sides；it is worthwhile to look at both before we commit ourselves to either．Exercises：
    回答下列问题：
    ①Why did the mule cock up her tail？
    ②Who was the mule's father？
    ③What can we learn from this fable⁵？