There were two cows in a field. The first cow said "moo" and the second cow said "baaaa." The first cow asked the second cow, "why did you say baaaa?" The second cow said, "I'm learning a foreign language."
Four. One to change it, one to sing about how heartbroken he is at the loss of the old one, one to sing about how madly in love he is with the new one, and one to go "Yee-Hah!" and throw his cowboy hat in the air.