All right. Because we're about to get to the hard part Sigh. All right.

第一层嵌套数组，好，很安静啊,大家有什么问题么？

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That's because, well, when you buy your first house you might be twenty-five, so thirty years brings you to age fifty-five; that's close enough to retirement.

这是因为,你可能在25岁时买第一套房子,当还清30年的贷款时你已经55岁了,都快退休了

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