You might choose to use a word for "Dog" as "Woof woof" because it sounds like a dog but you can't use a word for "Country" that sounds like a country.

你可以用"汪汪"这个词来表示"狗",因为它听起来像只狗,但你却无法使用一个听起来像国家的词,来表示"国家"

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