Hint: use anchors.

With your example, it appears you want to get rid of the first two digits and their following underscores that appear in the string. A regex that does that is: 

$string =~ s/^\d_(\D+?)\d_(.*)/$1$2/;

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the caret "^" at the beginning of this regex anchors things to the beginning of the string. You then make judicious use of captures to get the desired result.

Philosophy can be made out of anything. Or less -- Jerry A. Fodor

In reply to Re: changing only the first two matches of a regex by arturo
in thread changing only the first two matches of a regex by Anonymous Monk

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