Each vowel has a number of properties that distinguish it from other vowels.
SHAPE OF THE LIPS
CLOSE/OPEN or HIGH/LOW
SHORT and LONG
SHORT VOWELS
-Vowel sounds that are pronounced in a short form. In RP English the short vowel sounds are those in 'pet', 'pot', 'put', 'putt', 'pat' and 'pit', and the schwa sound.
LONG VOWELS
-Tends to be longer than short vowels in similar contexts
DIPTHONGS:
The most important feature of a diphthong is that it contains a glide from one vowel
quality to another one. BBC English contains a large number of diphthongs
there are:
-three ending in ɪ (eɪ, aɪ, ɔɪ)
- two ending in ʊ (əʊ, aʊ)
-three ending in ə (ɪə, eə, ʊə).