This is a common colloquial expression which originated in the ghettos and has reached mainstream middle class American society.

这是一个普遍使用的口语化表达，它起源于贫民区，并且流传到美国社会主流中产阶级。

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Gordon Brown's election strategists are now targeting "middle-class, mainstream mums".

现在，戈登·布朗的竞选策略指向了“中产阶级，主流妈妈”。

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Farmers like Mr. Lin hope that China's increasingly health-conscious middle class will help bring medicinal meats into the mainstream.

林文罗这样的农户希望，越来越重视健康问题的中国中产阶级会有助于中草药养殖的肉类成为主流。

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The Greens deserve some success, in part because of the way they have transformed themselves from hecklers standing on the sidelines of mainstream politics into a machine for representing Germany's clean-shaven middle class.

ECONOMIST: Power may change the Greens. That would be a good thing