hi there ,

i m new to unix , i d like to ask how can a get only even numbered lines matches with the word i search from txt file

for example :



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i want to grep (or any other commands ) the evenly number lines such as ;
.
.
.

3496:1.E.3. If an individual Project Gutenberg-tm electronic work is posted
3494:1.E.9.
3562:1.E.9. If you wish to charge a fee or distribute a Project Gutenberg-tm
.
.
.

i hope i m clear enough i tried many regular expressions but didn t work

THE PROBLEM IS PUNCTUATION ( : ) i believe bcus it reads them all as one string that makes it hard to seperate! , there might be other numbers in the line !

i don t know why this doesn t work grep -n '[0-9]*[08]*' list.txt