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grep- using regex to print all lines that do not contain a pattern (without -v)

How can I use regex, with grep, to print all lines that do not contain a pattern. I cannot use -v because I want to implement the regex within a much more complicated one, for which -v would be impractical.

But whenever I try to print lines that do not contain a pattern, I do not get the expected output.

For example, if I have this file:

blah blah blah hello world hello people something

And I…