Question

When I try to understand __ that prevent so many

When I try to understand __ that prevent so many Americans from being as happy as one might expect, it seems to me that There are two causes.
A. what it is B. Why it is

Answer 1

应该是选A what it is, 后面的 two causes 是两个原因 what 的回答才是原因 why it is 也可以只是不应该放在那个位置

追问

请问如果用Why it is ，这句话应该怎么写？

追答

如果用why it is 就要换一下 句子了 There seem to be two reason why so many Americans are not as happy as one might expect