/əʊ/ and /ɔ:/
/ɔ/ = short o：日本語の「オ」の口の形
/ɔ:/ = long o : 日本語の「オ」より口は大きい
taught caught brought
https://www.englishclub.com/pronunciation/minimal-pairs-o-or.htm
/ɔ/ = short o：日本語の「オ」の口の形
/ɔ:/ = long o : 日本語の「オ」より口は大きい
taught caught brought
https://www.englishclub.com/pronunciation/minimal-pairs-o-or.htm