Differences between the articulation of vowels and consonants.
The meaning of articulation is the production of speech sounds through the use of different vocal organs. In terms of articulation, there are two main differences between consonants and vowels. .
First, vowels and consonants can be distinguished by the degree of obstruction involved in it. For vowels, "phonetically, they are sounds articulated without a complete closure in the mouth or a degree of narrowing which would produce audible friction: the air escapes evenly over the centre of the tongue" (Crystal, 1991:376). You can see there is no obstruction of airflow for all vowels. On the other hand, consonants involve a certain degree of obstruction in terms of airflow. As Crystal notes, "phonetically, they are sounds made by a closure or narrowing in the vocal tract so that the airflow is either completely blocked, or so restricted that audible friction is produced" (74). The degree of airflow obstruction for consonants is varied. For plosive consonants like /p/, /t/ and /k/, there is a total obstruction of the airflow for a brief moment in sound producing process. However, for lateral consonant /l/ and approximants /r/, /w/ and /j/, they are produced without any obstruction of airflow. .
Next, vibration of vocal folds is necessary for the production of vowel sounds. The vibration of vocal folds refers to "the edges of the vocal folds are touching each other and the air passing through the glottis will usually cause vibration." (Roach, 1991:29) Therefore, all vowels are voiced. However, for consonants, vibration of vocal folds is not a must. The vocal folds can be wide apart and produce voiceless consonants like /p/, /t/ and /k/. The consonants can also be voiced like /b/, /d/ and /k/ with the touching of the vocal folds. Thus, we can conclude that the distinction of vowels and consonants can base on the varied vibration of the vocal folds during voicing.