http://www.bbc.co.uk/worldservice/learningenglish/grammar/pron/sounds/ - Go to this site and train vowels!!!
There are six vowel letters in the English alphabet: a, e, i, o, u, y. Vowel letters, alone or in combinations, represent from 15 to 22 vowel sounds, depending on the way of counting. All vowel sounds together are called the vowel system.
Vowels are speech sounds produced without obstructing the flow of air from the lungs, so that the breath stream passes freely through the mouth. Vowels are always voiced (i.e., the vocal cords vibrate). Syllables are formed by vowels. The English vowel phonemes fall into: MONOPHTHONGS,DIPHTHONGSand TRIPHTHONGS.
|Lips loosely spread. Tongue lax with less tension than / i: /||Pit|
|Lips loosely spread and slighly wider apart than / ɪ /||Pet|
|Lips neutrally open and slightly wider apart than / e /||Pat|
|Open lip-rounding, wide open jaws, back of tongue low.||Pot|
|Lips neutrally open. Open jaws. Centralized quality.||Luck|
|Lips loose, but closely rounded. Tongue not as tense as in / u: /||Good|
|Lips in neutral position. Centralized. Tongue slightly higher than in /ʌ/||Ago|
|Lips spread. Tongue tense (front raised) with sides touching upper molars.||Meat|
|Lips neutrally open and jaws far apart. Centre to back of tongue fully open.||Car|
|Medium lip rounding. Tongue drawn back making no contact with upper molars.||Door|
|Lips neutrally spread. Tongue slightly higher than /ə/ (no firm contact with upper molars)||Girl|
|Lips closely rounded. Back of tongue high. Tense compared with /ʊ/||Too|
|Note: schwa [ʃwɑː] лингв.нейтральный гласный [ə]|