[ou] - ground, hound, sound, around, out[au] - about[u:] - moon, soon, coat, road[u] - trouble, touch, country, cook, look, too[^] - boat
[ou] - ground, hound, sound, around, out
[au] - about
[u:] - moon, soon, coat, road
[u] - trouble, touch, country, cook, look, too
[^] - boat