What regular expression can match the particle "not" case-insensitively?

Question

Regular Expressions

Text:
To the woman we love, we forgive even her horns; to a woman whom we no longer love, we do not forgive even salted soup.

How to find two prepositions in it - separate "not", case insensitive? The preposition "not" is known in advance, that is, we search for exactly the given preposition, in this case - "not".

Answer 1

[Hn][Her]