The /ɔ/ vowel is spelled <a>, <al>, <au>, <or> or <aw>. The /ʊ/ vowel is spelled <oo> or <u>.
One of the sounds is long and the other short. Although they are fairly close in tongue position, they should not cause problems for learners.
Interesting pairs include:
gaudy goodie
hawker hookah
warden wooden
The density figure is 3.37%. The set makes 31 semantic contrasts giving a loading of 47%.
balk book balked booked balking booking balks books ball bull balls bulls borsch bush bortsch butch calk cook calked cooked calking cooking calks cooks cawed could cork cook corked cooked corking cooking corks cooks corker cooker corkers cookers fall full Fawley fully fort foot forts foots gaud good gauds goods gaudy goody gaudies goodies hawed hood hawk hook hawked hooked hawking hooking hawks hooks hawker hookah hawkers hookahs hawker hooker hawker hookers hoard hood hoarded hooded hoarding hooding hoards hoods horde hood hordes hoods outport output pall pull palled pulled palling pulling palls pulls Paul pull pawed pud porches putsches port put ports puts shored should sort soot sorted sooted sorting sooting sorts soots stored stood talk took wall wool walls wools ward wood wards woods warded wooded warden wooden Warley woolly
John Higgins, Shaftesbury, November 2009