perceive与as搭配时，其意为“看待，理解”，此时它是及物动词，即其后要接宾语（perceive…as…），不存在你说的“perceive一定是属于前面的某个从句”的问题。下面是几个相关例句，注意体会可以解决你的问题：

She began to perceive him as a loser. 她开始把他看作是一个失败者。

I perceived her statement as a threat. 我把她的声明看成是威胁。

这类用法还通常用于被动式。如：

New technology is often perceived as a threat. 新技术常被看作是一种威胁。

The General’s words were perceived as a threat by neighbouring countries. 将军说的话被邻国看作是一种威胁。

Even as a young woman she had been perceived as a future chief executive. 甚至是在年轻时，她就被看作是未来的总裁。

It is widely perceived as a women’s health problem, but it does also affect men. 这被广泛看作是女性健康问题，但实际上也影响男性。