有个问题，但她无法确切指出是什么。

There was an issue, but she couldn't ___put ___her ___finger ___on it.

他感觉到有些奇怪，但无法确切指出原因。

He sensed something odd, but he couldn't ___put ___his ___finger ___on the cause.

尽管她很专业，但无法确切指出项目失败的原因。

Despite her expertise, she couldn't ___put ___her ___finger ___on why the project failed.