Online PHP editor | refs for mYb90

<?php $txt = 'dog blah crocodile blah dog blah cat blah crocodile blah dog blah crocodile blah dog blah cat blah dog blah cat blah crocodile blah dog blah crocodile blah mice blah cat blah crocodile'; echo preg_replace('/(?:dog|mice)(?:(?!dog|mice|cat).)* \Kcrocodile(?= (?:(?!dog|mice|cat).)* (?:dog|mice))/', 'replacement', $txt);