Full has a vowel sound like "but". b - u - t Fool has a vowel sound like "you" y - oo

You might like this site: http://www.manythings.org/pp/ It doesn't have the u/u: sounds though :P ******* Edit: Check these: http://tfd.com/fool http://tfd.com/full (click on the icon next to the word) If you haven't yet, I'd recommend that you memorise the IPA symbols: http://en.wikipedia.org/wiki/International_Phonetic_Alphabet http://www.stuff.co.uk/calcul_nd.htm it'll make your life easier.

"Full" is said very fast and short, while the vowel sound of "fool" is more extracted - "fo~ol".

Fool tends to linger a little longer

I guess you can say the vowel in "full" is shorter than the vowel "fool"