President Obama faces united Republican opposition to his health care reform plan, which would expand coverage to some 30 million more Americans, and take steps such as ending insurance company practices of denying coverage for pre-existing medical conditions.

VOA: standard.2010.03.10

On the next step though, this, we get substituted by that. Right, on the next step, I'm back in the even case, it's going to take six more steps, plus t of b minus 1. Oops, sorry about that, over 2.

这一步就是偶数了，这一步会让我们得到，6+t这样的结果，因为b-1现在是偶数了,别忽略这里的细节。

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