a Vowels are sounds produced without obstruction of the air stream in the mouth in producing them there is vibration of the vocal cords, so all vowels are voiced In English there are twenty vowels in all a Consonants are sounds produced by some form of obstruction of the air passage and be either voiced or voiceless There are twenty-eight consonants in English☆ Vowels are sounds produced without obstruction of the air stream in the mouth. In producing them there is vibration of the vocal cords, so all vowels are voiced . In English there are twenty vowels in all. ☆ Consonants are sounds produced by some form of obstruction of the air passage and be either voiced or voiceless . There are twenty-eight consonants in English