Vowels and Consonants

Although Vowels and consonants are very familiar to us,they are ,however, hard to define if we attempt to study these speech sounds in a scientific way .The most common view is that vowels are speech sounds in which the air is being obstructed as it passes from larynx to the lips. Have you ever wondered why a doctor asks us to open our mouth and say “ Ah “? By producing such a vowel sound, the doctor will know whether the air is obstructed .But if we make a sound like /s/,which is a consonant sound,we clearly feel that we are making it difficult or impossible for the air to pass through the mouth. In this respect,consonants are speech sounds in which the air is obstructed.Most people would have no doubt that sounds like /s/,/z/,/t/, /d / should be called consonants.;nevertheless,it is no easy to make a decision since there are many cases in which some English sounds that we think of as consonants, such as the sounds /h/ and /w/ are not, and therein lies the rub.The former sounds do not really obstruct the flow of air more than some vowels do.As a term,they are called semi-vowels : sounds like vowels but function as consonants . Another problem is that sounds are treated differently ,a consonant can be a vowel in another language;for instance, /r/ sound ' is felt to be a consonant by most English speakers, but in some other languages such as Mandarin Chinese is a vowel.This is the kernel of disagreement. We think that the difference between vowels and consonants is a difference in the way that they are produced, and this is inevitable. It is possible to establish two distinct groups of sounds (vowels and consonants) in another way.