For example, a* is the letter "a" zero or multiple times, a+ is the letter "a" at least once, a{3} is "aaa", a{1,3} is the letter "a" at least once but not more than three times.

例如，a* 表示字母 “a” 出现零次或多次，a+ 表示字母 “a” 出现至少一次，a{3} 表示 “aaa”，a{1,3} 表示字母 “a” 出现至少一次但不多于三次。

youdao

If America actually loses its AAA, some investors who are obliged to own only AAA-rated paper might have to sell.

如果美国真的失去AAA级，那么一些只能持有AAA级债券的投资者就可能不得不卖出。

youdao

Or, if even that is impossible, could the six AAA-rated members of the euro zone bind themselves together?

还是，如果连这也不可能，只有欧元区六个AAA等级的成员国抱成团？

youdao

The securities carried AAA ratings, and yet offered much higher yields than other AAA-rated, non-MBS securities.

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Because they were AAA-rated and yielded a premium over the banks' cost of capital.

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The U.S. has not been a AAA-rated nation in the absolute sense for a while.

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