[If there was] an undesignated pair [of obligatory bird-offerings] and a predesignated pair [of such offerings], [and a bird] flew from the undesignated pair to the designated pair, [then] he shall take a pair-mate for the second [bird of the undesignated pair]. [If a bird then] returned, or if [a bird] flew initially from the designated pair [into the undesignated pair], [then] they must all be left to die.