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    A bag is useful and the word "bag" is useful, too. Here is an interesting phrase, "to let the cat out of the bag". In meaning it is the same as "to tell the secret". And there is an old interesting story about it. Long ago, when farmers wanted to sell chickens at the market, they would usually throw the chickens in cloth bags. But cats were cheaper than chickens at that time, so many farmers would put cats into the cloth bags but not chickens.

    One day, a woman asked a man for a chicken. The man gave her a cloth bag in which there was a cat. The woman begged to see the chicken. When the man opened the cloth bag, a big black cat ran out. Not a chicken! The man's secret was out and everyone knew it.

    Now when we say someone gives away a secret, we say "he lets the cat out of the bag". And that is the story where the interesting phrase came from.

假如你是红星中学李华，你的一位外国朋友所在的杂志社正在开展改进社会风气活动，请你根据下列要点，用英文写一篇征文。

1).不守公德现象;      2). 改进的方法；     3). 呼吁。

注意：

1)．词数100左右；    2)．可以适当增加细节，以使行文连贯；

关于x的一元二次方程（a﹣5）x²﹣4x﹣1=0有实数根，则a满足（　　）