she swam to the shore having spent the night in the water??,请问，having spent 是怎么回事，

Question

have 加ing ，又过去分词，这是什么语法形式，如何理解

Answer 1

1. having spent the night in the water为现在分词短语做时间状语。
翻译为：在水里呆了一夜之后，她游向岸边/海滨。

2. having spent the night in the water其实是现在分词短语的完成形式，其一般式是spending the night in the water。
因为句子主语（即spend的逻辑主语）和非谓语动词spend之间为主动关系，所以用其现在分词形式。
又因为spend the night...该动作发生在谓语动词swam to the shore之前，所以进一步使用现在分词的完成形式having spent...

参考资料：英语牛人团

Answer 2

（已经）在水中过了一夜以后
ing形式做状语

Answer 3

having spent =
after she had spent the night