When at last we were all assembled4, waiting for dinner to be announced5, I1 reflected2, while I chatted with the woman I had been asked to "take in"6, that civilised man practises a strange ingenuity in wasting on tedious exercises the brief span of his life3.

长难句解析

解：1主语，2谓语，3宾语从句，4时间状语从句，5介词短语作状语，6时间状语从句

析：宾语从句3中包含两个固定搭配，“practise in doing”练习做某事，和“waste A on B”把A浪费在B上，在这里作者把A后置了，放在了B的后面。

重点词汇词组

1.ingenuity 聪明才智，善于创新，足智多谋

eg.Ingenuity and hard work pays off at last.

心灵手巧与勤奋工作终有回报。

2.span v.跨越；持续 n.跨度；范围；持续的时间

eg.Children usually have a short span of concentration.

孩子们注意力集中的时间通常很短。

【常见搭配】spick and span 崭新的，极干净的

eg.She always keeps her kitchen spick and span.

她总是把厨房收拾得干干净净的。

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