Question

He regretted forgetting___was his mother's birthday and saying Happy Birthday to her

He regretted forgetting___was his mother's birthday and saying Happy Birthday to her
A that B which C it Dwhat 为什么选C 求高手解答详细一点 谢谢！

Answer 1

c He regretted forgetting (that) it was his mother's birthday and saying Happy Birthday to her
这里我们看到AND 前后并列的其实是forget和say。他很遗忘忘记了，忘记了什么？忘记了一件事，用that引导的宾语从句，that省略。A后面的句子没有主语，就是缺it，B不是非限制定语从句干嘛用which，D不能用what引导和不合句意。其实 也可以直接用when

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但是it在整句中 替代的是哪个？

追答

亲~代替his mother's birthday，作为形势主语

Answer 2

翻译：他对忘记了母亲的生日和对她说生日快乐这件事感到抱歉。