1. His absence from the graduation ceremony was the greatest regret of his life. 2. His no attdnding the graduation ceremony was the greatest regret of his life.
以上两句，不同，就是，主语，第1句，主语用了absence from这个短语，假如我一下子想不起来这个短语了，我能不能用attend的动名词形式？也就是说his absence=his no attending,它们之间是否等同的？能不能如此互换？互换时，应该注意什么？
“缺席毕业典礼是他一生最大的遗憾。”
这个句子的重要地方，是对主语的翻译。“缺席毕业典礼”就是“未能参加毕业典礼”。“他一生中” 用in his life。可以有如下几种翻译：
His absence from the graduation ceremony was the greatest regret in his life.
（用名词 His absence）
His failure to attend the graduation ceremony was the greatest regret in his life.
（用名词加不定式 His failure to attend）
His not attending the graduation ceremony was the greatest regret in his life.
（用动名词的复合结构，注意表达：one’s doing... 或one’s not doing...，不是ones no doing...）
用主语从句翻译（it作形式主语）：
It was the greatest regret in his life that he had been absent from the graduation ceremony.
It was the greatest regret in his life that he had not attended the graduation ceremony.
