Those are the two biggest rating agencies in the U.S. today and they're extremely powerful organizations because they --Standard & Poor's also does letter grades, a slightly different system, but almost the same.

如今他们是美国最大的两家评级机构,而且他们是非常权威的组织,标准普尔也进行字母评级,体系上有些区别,但基本相同

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