SAS VTA: Filtering words that are preceded by reverse words

[ChenB]

Hello everyone,
I'm trying to filter files that have a good word and a word that changes its meaning does not appear before it.
I have a concept of good_words and a concept of changing_words and I want the system to find for me the good_words that do not appear before the changing_words
for example:
Today is a beautiful day - will appear
Today is not a good day - will not appear.
Do you have any suggestions for a solution?
Thank you!!

[Madelyn_SAS]

Does it have to specifically be words in a certain position, or can you just come up with a list of words like "not" that could be filtered regardless of location?  If so, could you simply create a filter like: 

( 'Comment'n NotContains UpCase(not') )