vowels

I was taught in grammer school that the vowels are; a e i o u and sometimes y and w. Is W considered a vowel sometimes? Can you give me an example, please?
Daniel
dhw52@myphotomax.com

When w follows o, and the o says it's name, the w is acting like a vowel (follows double vowel rule)


In these words: cow, town, brown, etc., w is a consonant.


In these words: tow, low, bowl, etc., w is a vowel. Notice the o is long and the w is silent.