一个英语句子的翻译------------高手帮忙

Question

What he particularly wanted to investigate was how ichthyosaurs adapted to the problem of decompression over the 150 million years.
分析句子结构，然后翻译，谢谢

Answer 1

What he particularly wanted to investigate——what引导主语从句做主语。
how ichthyosaurs adapted to the problem of decompression over the 150 million years——how引导宾语从句做宾语。

翻译：他特别想去调查，鱼龙是如何在1亿5千万年间适应减压的难题的。

Answer 2

What he particularly wanted to investigate was how ichthyosaurs adapted to the problem of decompression over the 150 million years.
主语：What he particularly wanted to investigate
谓语：was
宾语：how引导的宾语从句，how ichthyosaurs adapted to the problem of decompression over the 150 million years
翻译：
他特别想调查的是鱼龙是怎样适应1.5亿年前减压的问题。本回答被提问者采纳

Answer 3

他特别想调查的 是 超过一亿五千万年来，鱼龙是如何适应（解决）减压问题的。