How to add tags to negated words in strings that follow “not”, “no” and “never”

Question

How do I add the tag NEG_ to all words that follow not, no and never until the next punctuation mark in a string(used for

Answer 1

You will need to do this in several steps (at least in Python - .NET languages can use a regex engine that has more capabilities):

• First, match a part of a string starting with not, no or never. The regex \b(?:not?|never)\b([^.,:;!?]+) would be a good starting point. You might need to add more punctuation characters to that list if they occur in your texts.

• Then, use the match result's group 1 as the target of your second step: Find all words (for example by splitting on whitespace and/or punctuation) and prepend NEG_ to them.

• Join the string together again and insert the result in your original string in the place of the first regex's match.