Letter on position 1 (b) changed: 9 words coos doos goos loos moos poos roos woos zoos Letter on position 2 (o) changed: 2 words bios bros Letter on position 3 (o) changed: 13 words boas bobs bods bogs bohs bois boks bops bors boss bots bows boys Letter on position 4 (s) changed: 8 words boob booh book bool boom boon boor boot