Vowel Sound Effects
The main vowels are ‘a’, ‘e’, ‘i’, ‘o’, and ‘u’, although ‘w’ and ‘y’ can sometimes produce vowel sounds. All vowels can either be pronounced long or short:
Long: ‘ay’ as in ‘hay’
Short: ‘a’ as in ‘cat’
Lots of short vowels together tend to increase pace and give a sense of hurry or panic whereas repeated long vowels can often slow a line down and make it sound more relaxed or perhaps sad and weary.
An example of this can be found in the opening lines of this song from The Sound of Music, which, although it is a song about saying goodbye still manages to be sung cheerily by the Von Trapp children because of the short vowel sounds. In fact the song isn’t really a sad one at all because the children are only saying goodbye because it’s time for bed:
So long. Farewell. Aufwiedersehen. Goodbye.
In contrast, the long vowels in the following speech make it sound world weary and depressing:
Oh, woe is me, with hurt I moan and cry
Life holds no more, I’ll surely die.
Notice how in both cases the sounds support the meanings of the lines.
The repetition of vowel sounds is called assonance.