同学你好，该知识点来自沪江网校《新概念英语第二册【惠学班】》的课程，想要更系统的学习，欢迎进入课程学习。不仅可以和更多的同学一起学习，而且还有老师、助教随时的学习指导和知识点解答哦。

同学你好：
But this does not matter, for, as he has often remarked, one is never too old to learn.
这里的as he has often remarked是插入语，所以前后都需要逗号隔开
同学在分析的时候可以先不看这部分。
But this does not matter for one is never too old to learn. 这里的for表原因，前面用逗号隔开更清晰；
翻译：但这并不重要，因为一个人永远不会太老而无法学习。
But this does not matter, for, as he has often remarked, one is never too old to learn.
整句翻译：但这并不重要，因为这正如他经常说的“一个人永远不会太老而无法学习。”
as是连词，表示：像...

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