whew / whoo / woo [wu:]
whew – n. & v. – n. a sound like a half-formed whistle uttered as an exclamation; v. – 1. make a whistling noise; 2. utter an exclamation; 3. move quickly
whoo – v. – hoot
woo – v. – 1. solicit to gain favour; 2. court; 3. make pleading invitations