The Consonantal Divide, 2

       All right, if the consonant "w" is made up of two u's, a double-u, how so? 

       Produce the sound the letter makes when it begins a word, [w].  You purse your lips and start to say something like "ooh," then merge into a second sound that's something like "uh."  It's a diphthong consisting of those two sounds.

       In fact, it's two slightly different pronunciations of the vowel "u."  It's the "ooh" sound in words like June, tuba, ludicrous,  lubricate, illuminate, plus the "uh" sound as in sun, run,  jump, rub-a-dub-dub, three men in a tub.  Strange to say, but there really are two different vowel sounds merged in that single consonant "w."

       That is why "w" is often called a "semi-vowel."