For instance, we have made changes to our criteria for rating mortgage securities so that it will be much more difficult for such a security to receive a triple-A rating.
我们对住房贷款抵押证券评级标准作出调整，使得这些债券更难获得AAA级评级。
2
It involved a complex synthetic security derived from existing mortgage-backed securities by cloning them into imaginary units that mimicked the originals.
它涉及一种复杂的合成证券，源自于将现有的抵押贷款证券“克隆”成模仿原型的虚构单位。
3
Banks were quick to see a market based on accepting ITINs rather than social-security Numbers as identification for mortgage loans.