How now brown cow
"How now brown cow" () is a phrase used in elocution teaching to demonstrate rounded vowel sounds. Each "ow" sound in the phrase represents the diphthong /aʊ/. Although spelled "ow" in these four words, this same diphthong is also spelled "ou". Some examples of these homophonic /aʊ/s are the English words "house", "blouse", "noun", and "cloud". The use of the phrase "how now brown cow" in teaching elocution can be traced back to at least 1926. The phrase "how now" itself is an archaic greeting or interrogative expression.