No More Sad Tunes
The VCe long /u/ vowel spelling as in cube is only one spelling of the long /u/ vowel sound. There are other spellings of the long /u/ vowel sound. These include oo as in moon, ui as in suit, ou as in soup, and ough as in through. In some cases, this VCe pattern does not represent the long /u/ vowel sound, as in assure, treasure, and pressure.
Please note: There is some debate about whether the sound in words like cube is the same as the sound in words like flute because of a slight difference in pronunciation.