Since you haven't provided any code, how about some pseudocode to get you started? 
OPEN file1
READ contents of file1 into array @words

OPEN file2
FOR line in file 2
    IF line contains any of @words
        PRINT "#" + line
    ELSE
        PRINT line

[download]
You might want to check out the documentation for open and perlretut.

In reply to Re: how to comment the lines if found a match by lostjimmy
in thread how to comment the lines if found a match by kavitha

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