sentences:  The song of the male barn swallow is a cheerful warble, often ending with "su-seer" with the second note higher than the first but falling in pitch.Calls include "witt" or "witt-witt" and a loud "splee-plink" when excited (or trying to chase intruders away from the nest).The alarm calls include a sharp "siflitt" for predators like cats and a "flitt-flitt" for birds of prey like the hobby.