ABSTRACT
Vowels can be distinguished definitionally from consonants as having a relatively open aperture of articulation. All vowels are more open in aperture than all consonants. The class of sonorant sounds, which includes voiced vowels, nasal consonants and voiced approximants, is opposed to the class of obstruent sounds. Of all the sonorants, vowels have the greatest sonority. The English vowel system includes both monophthongs and diphthongs. In the production of monophthongs, the tongue remains in a relatively unchanging position throughout articulation. The tendency to weaken vowels towards schwa in conversational English seems to be a difficult aspect of English to learn for most non-native speakers, possibly in part because of an over-reliance on spelling as a guide to pronunciation. Chart the vowel system of another language or variety and describe the similarities and differences between that vowel system and your own variety of English.
