How to find a sentence containing a phrase in text using python re?

Question

I have a text that is a sentence, some of which are questions. I am trying to create a regular expression that will only retrieve questions that contain a specific phrase, namely "NSF":

import re
s = "This is a string. Is this a question? This isn't a question about NSF. Is this one about NSF? This one is a question about NSF but is it longer?"

Ideally, re.findall will return:

['Is this one about NSF?','This one is a question about NSF but is it longer?']

but my best attempt:

re.findall('([\.\?].*?NSF.*\?)+?',s)
[". Is this a question? This isn't a question about NSF. Is this one about NSF? This one is a question about NSF but is it longer?"]

I know that I need to do something with the non-greedy, but I'm not sure where I got confused.

Answer 1

: , , , OP, . nltk (. this ).

, , , , , , , , , , , . , .

\s*([^!.?]*?NSF[^!.?]*?[?])

regex.

• \s* - 0+
• ([^!.?]*?NSF[^.?]*?[?]) - 1
  • [^!.?]*? - 0+, ., ! ?,
  • NSF - , , NSF
  • [^.?]*? - .
  • [?] - ? ( \?)