I can't help but think there is more to this requirement than you've specifed, but based on what you've asked for, +a little bit more, try:

/\s\d{3,4}\s/ and print for 'abd 123 fred', '555-5555-6666', 'ab 12345
+ xd';;
abd 123 fred

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In reply to Re: Recognizing 3 and 4 digit number by BrowserUk
in thread Recognizing 3 and 4 digit number by htmanning

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