I don't know if the subject makes a lot of sense, but I don't quite know how to explain what I'm trying to do in a title, and I've searched a lot for answers.

So, for example, if someone sends a line of text saying:

"This is an example"

and I have a .txt file called keywords.txt which has a list of words, such as
Code:
test
example
word

How would I write a script that would go through the text file (by line) searching for a match in the message?
I imagined it would be something along the line of the following, but with some sort of loop for each line.
Code:
on *:text:*:* {
  if (read(keywords.txt, nw, ???) isin $1-)
  msg # You said a keyword.
}