Vowels and consonants are the two main types of sounds in English. In writing, these sounds are represented by letters, but a single letter can sometimes represent more than one sound. They are symbols that let the reader know what a word should sound like. When humans speak, air flows through the vocal cords and is altered to change how sounds come out. These sounds are ascribed to different letters. How these sounds are articulated determines whether they are considered vowels or consonants.
Vowels and Consonants
Speech Sounds
As words are articulated, air flows through the vocal cords and is manipulated to create different sounds. This manipulation can occur in the vocal cord itself, as well as in the mouth with the the help of teeth, lips, and the tongue. Some speech sounds are produced without any closure of the airflow. These are what we call vowels. All other speech sounds, those with alteration or blockage of airflow, are called consonants.
Vowels
It’s easy to remember that the letters A, E, I, O, U, and sometimes Y are vowels. They are all speech sounds without any blockage of airflow. Try saying these letters out loud and you will notice that the vocal cords are left open–the tongue, teeth, and lips do not block any air. By contrast, try a consonant like the letter B. In order to articulate the speech sound represented by the letter B, you must fully close your lips and then release the airflow.
The letter Y is where vowels and consonants overlap. Determining how the letter functions within a word depends on whether it articulates airflow in the manner of a vowel or a consonant. Typically, if Y is the only vowel in a word, it is considered a vowel. Also, if Y ends a word or a syllable, like in the word “play,” it is a vowel. When Y is the first letter of a word or syllable, it requires blockage of the airflow to pronounce, thus making it a consonant. Examples of Y as a consonant include the words “yearn” and “beyond.”
Consonants
There are different types of consonants depending on how they function in a word.
- Digraph consonants are paired together to represent a new speech sound. For example, the digraph CH represents the speech sound of words like “change” and “catch.” The sound that CH makes is not the same as the sounds that C and H make separately.
- Successive consonants look similar to digraphs in that they are two consonants paired together, but they don’t create a new sound. Rather, when successive consonants appear in a word, both of the sounds are articulated. Take, for example, the word “speech.” Unlike with digraph “CH” where the two consonants represent an entirely different sound, the successive consonants “SP” require both sounds to be articulated and blended together.
- There are also pairs of consonants where one speech sound is silent. This can occur when the same letter appears twice in a word. For example, in the word “summer,” only one M sound is articulated. Other commonly used silent consonants are words with the pairs KN, as in “knight,” BT, as in “doubt,” PT, as in “pterodactyl,” PS, as in “psychedelic,” and PN, as in “pneumatic.” For all of these, we encounter situations in which one of the two speech sounds takes precedence over the other, leaving one silent. This does not mean the silent consonant is a vowel, however. It remains a consonant and is simply not articulated.
- The final type of consonant is a stop consonant, or an oral occlusive. These break up a word or add emphasis by causing a pause in airflow. In the case of “plosives,” the airflow is paused and then causes a dramatic release. Stop consonants help give variation and definition to the articulation of words. The word “crack,” for example, includes a stop consonant with the letter K. When pronounced, the K leaves a lingering pause in airflow that adds emphasis to the word.
Key Differences
| Feature | Vowels | Consonants |
|---|---|---|
| Airflow | Unrestricted | Restricted or blocked |
| Letters | A, E, I, O, U (and sometimes Y) | B, C, D, F, G, H, etc. |
| Role in Syllables | The core of a syllable | Supports vowels to form syllables |
| Vocal Cord Use | Always voiced | Can be voiced or voiceless |
Understanding the difference between vowels and consonants just takes a simple test of pronouncing the letters within each word and seeing how the air is altered in your vocal cords. Though complex in their origin, vowels and consonants are symbols created to make reading and speaking easier.