But even he was unable to discover how long the gorilla lives,or how or why it dies,nor was he able to define the exact social patterns of the family groups,or indicate the final extent of their intelligence.
答案：
要點：本句前半句中or how or why it dies位于表示否定意義的unable后，相當于and he was unable to discover how it dies and he was unable to discover why it dies,翻譯時將這里的or譯為“以及”，更合乎漢語習慣。后半句中nor后面的or不宜譯為“或者”，而應將or indicate譯為“也未能說明”。nor was he...為倒裝結構。

譯文：可是連他也未能弄清楚大猩猩能活多久、怎樣死亡以及死亡的原因是什么，他也不能肯定其家族群居的確切方式，也未能說明它們智力的最高程度。