分析：首先，這是壹個由and引導的並列句
The idea that government should regulate intellectual property through copyrights and patents is relatively recent in human history.
在這句話裏：the idea 作主語that government should regulate intellectual property through copyrights and patents做同位語說明idea.
is relatively recent in human history做表語
在the precise details of what intellectual property is protected for and how long vary across nations and occasionally change.這句話中
the precise details of what intellectual property is protected for and how long 做主語，其中what intellectual property is protected for how long 做of的賓語。
vary across nations and occasionally change作謂語。
2. 其實an 在這裏是習慣用法，表示在....中（壹般是壹群人、壹堆東西），舉例子時常用
還有類似的
an inspected 1000 objects 在受檢查的這1000個物品中
an arrested 100 criminals 在被逮捕的100名罪犯裏