1. What does this comment mean?

  # look for b e n(regardless of intervening characters)
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2. Keep in mind that what you're saying is: Process each file found in @ARGV. For each such file, analyze each line in turn and print out the entire line if the line as a whole matches the pattern.

Example: Create a file called abort and add it to @ARGV. Type one line of text into that file:

zzzzzaxbxoxrxt caxton
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Re-run the script and ask yourself if that's what you were looking for. HTH!