Consider the line: “my heart grew sick;
it was the dampness of the catacombs
that made it so." (paragraph 89) what
insight into the narrator's point of view
does this line likely provide the reader?
cite evidence from the story to support
your response.
from the story the cask of amontillado.

This line shows the reader that Montressor still has dark feelings about Fortunato and what he did to him.

We can arrive at this answer because:

These feelings didn't dissipate even after Montressor concluded his revenge, as he says that his heart has become sick from the dampness of the catacombs.

More information:

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That he has lack of self-knowledge and it is showing the readers that he has emotions.

Explanation:

We can find this line at the end of the story ''The Cask of Amontillado'' where Montresor has locked down his enemy Fortunato and it was looking like he was dead because he didn't give any response behind that brick wall where he was.

''But to these words, I hearkened in vain for a reply. I grew impatient. I called aloud -- "Fortunato!" No answer. I called again -- "Fortunato!" No answer still. I thrust a torch through the remaining aperture and let it fall within. There came forth in return only a jingling of the bells. ''

its structered sequentially i think