Recently, however, there is a bit of a scandal regarding these rating agencies because they gave AAA ratings to some subprime securities.

但是,最近,出现了一点关于评级机构的丑闻,因为他们将一些次级证券评为AAA级

耶鲁公开课 - 金融市场课程节选

Then, if you weren't quite Aaa, you were Aa and if you weren't quite Aa, you were A and then you could become Ba.

于是,如果你达不到AAA,你就会是AA,如果你达不到AA,你就会是A,再往下就有可能是BA

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