The consonants of American English are usually described and classified according to the 1) manner in which they are produced (stops, fricative, affricates, nasals, liquids, and glides), 2) place of production in the mouth (lips, teeth, gums, and palate or roof of the mouth), and 3) presence or absence of voicing.
Voiced and Unvoiced Consonants
All consonants are either: voiced or unvoiced. Voiced consonants are produced by the vibration of the vocal cords, and unvoiced consonants are produced by the lack of such vibration. Consider the /p/ and /b/, for example, and say the words “pack” and “back.”. Notice that your lips come together and explode the air in exactly the same way for the /p/ and /b/. The only difference between these two sounds is that the /p/ is produced without voice and /b/ is made with voice.
Similarly, the /s/ and /z/ in the words “Sue” and “zoo” are produced alike, except that the /s/ is voiceless and the /z/ is voiced. This difference is easy to feel if you put your hand on your throat and make the sounds /s/ and /z/. Be sure that you do not pronounce the letter S and Z, but actually make the sound, like this: “ssss” and “zzzz”. Notice that you feel the same sort of vibration for the /z/ as you did for the vowel sounds “ah” and “ee”, but there is no vibration for the /s/.
Stop Consonants /p,b/, /t,d/, /k,g/, are called “Stops” because to produce each one, you must stop the air stream completely, then release it into a little explosion. This group of sounds is divided into three sub-groupings according to the place of production. The /p,b/ are made by stopping the air with the lips and then releasing them suddenly. The /t,d/ are made by stopping the air with the tip of the tongue in contact with the upper gum behind the teeth, then releasing the tongue. The /k,g/ are produced by placing the back of the tongue in contact with the back portion of the roof of the mouth (velum), and then releasing the tongue to let the air escape.
The next group of sounds, /f,v/, /θ,ð/, /s,z/ /ʃ,ʒ/ is called “Frictions” because the air stream is forced through a narrow passage in the mouth which creates a friction or hissing sound. Sometimes these sounds are also called “Continuants” because they can be continued or prolonged. Compare this feature with the “Stops” which cannot be prolonged or continued.
The Frictions are sub-divided into four groups according to their place of production as follows:
1) /f,v/ are produced by forcing the air through a narrow opening formed by placing the lower lip lightly against the upper teeth ;
2) the /θ,ð/ are made by putting the tongue tip between the teeth and forcing the air between the tongue and upper teeth;
3) the /s,z/ are produced by forcing the air between the tip of the tongue and the upper gum ridge, similar to the position for the /t,d/, except complete contact is not made;
4) the /ʃ,ʒ/, are made by forcing the air between the front portion (blade) of the tongue and the roof of the mouth slightly behind the upper gum ridge. The /ʒ/ sound does not occur at the beginning of words and appears only in a few words borrowed from French.
The two sounds /tʃ,dʒ/ which make up this group are composed of a stop and a friction sound blended together to form a single sound. The /tʃ/, is composed of the stop /t/ and the friction /ʃ/, and the /dʒ/ is composed of the stop /d/ and the friction /ʒ/. To illustrate, try producing the initial /tʃ/ sound the word “church”, and you will notice that your tongue starts out in the same position as for the /t/. Now, prolong or lengthen the final /tʃ/ sound in the word “church” and you will discover that you can only prolong the friction /ʃ/.
The three nasal sounds /m, n, ŋ/ making up this group are called “Nasals” because the air stream is directed through the nose. This is accomplished by blocking the passage of air through the mouth and lowering the velum (back portion of the roof of the mouth) so the air escapes through the nose. The /m/ is formed with the lips together in the same position as for the /p,b/. The /n/ is formed with the tongue tip in contact with the upper gum ridge in the same position as for the /t,d/. The /ŋ/ is formed by placing the back of the tongue in contact with the velum in the same position as for the /k,g/. In English, the /ŋ/ never occurs at the beginning of words. All of the Nasals are produced with voice and, like the Frictions, they can be continued for as long as the breath holds out.
The two sounds /r/ and /l/ composing this group have some features of both consonants and vowels and, therefore, are also called semi-vowels.
The /r/ sound is called a retroflexive consonant because the tip of the tongue is curled upwards and pointed towards the roof of the mouth just behind the gum ridge. In spelling, the letter “r” is used both for the /r/-consonant and the /r/-vowel. Phonetically, the /r/-vowel is represented as /ɜ ̂/ when it is in a stressed syllable and as /ɚ/ when in unstressed syllables. If you prolong the /r/-consonant, as in “red”, it will have the /r/ quality of the /r/-vowel. One important distinction between the two is that the /r/-consonant is not syllabic, i.e., it cannot form the core of a syllable or stand-alone. Also, unlike the /r/-vowel, the /r/-consonant does not occur at the end of words.
The /l/ sound is produced by placing the tongue tip on the upper gum ridge in the same position as the /t,d/ and directing the air stream over one or both sides of the tongue. Because the air escapes from the side of the tongue, this sound is also called a lateral consonant. When the /l/ occurs at the end of a word (as in “ball”) or before another consonant (as in “milk”) it has a different quality from the /l/ at the beginning of a word (as in “like”) or after another consonant (as in “please”). The /l/ in “ball” and “milk” is sometimes called a “dark /l/ ” and is produced by raising the back of the tongue in addition to the contact between the tongue tip and the gum ridge.
The two sounds /j,w/ are called glides because they are transitional sounds which move or “glide” towards the vowel sound that follows. Like the /r,l/, the glides have characteristics of both consonants and vowels and are also called semi-vowels. Technically, the /h/ is a friction sound, rather than a glide, but it is included with this group because it takes on the quality of the vowel that follows.
The /j/ sound is formed by raising the front portion of the tongue (blade) toward the roof of the mouth, slightly behind the upper gum ridge, and then moving toward the position of whatever vowel that follows. The starting position of this sound is quite similar to that of the /ʃ,ʒ/, except the actual formation of the sound is characterized by the motion towards the vowel, rather than by position. The /j/ sound occurs only at the beginning and middle of words.
The /w/ sound is formed by rounding the lips, raising the back of the tongue, and then moving toward the vowel that follows. The starting position of this sound is similar to the vowel /u/, as in the word “moon”. Like the /j/, the /w/ is characterized by the movement towards the vowel and also occurs only at the beginning and middle of words.
The /h/ is a voiceless friction sound which is produced by exhaling the unvocalized breath stream in a slight puff, with the vocal cords close enough together to produce audible friction, but no voicing. Otherwise, it has no characteristic mouth position, but takes on the position of the vowel or glide that follows it. This sound only occurs at the beginning of a word or syllable. In spelling, the letter “h” is often silent, as in the words “this, hour, child”, and when it appears at the end of a word, it is never pronounced, as in the words “oh” and “enough”.
Consonant blends are combinations of two or three consonants, which are, produced one after the other without being separated by vowels. Sometimes they are also called consonant clusters. For purposes of this program, we will refer to combinations of consonant at the beginnings of words as consonant blends, and those at the ends of words, as consonant clusters.
There are four categories of Consonant Blends; /r/-blends, /l/-blends, /s/-blends, and three-element blends. For example, the /r/-blend “/pr/”, as in the word “pretty”, is produced by combining the /p/ and /r/. The /l/-blend “/pl/”, as in the word “please”, is produced by combining the /p/ and /l/. The /s/ -blend “/sp/”, as in the word “spell”, is produced by combining the /s/ and /p/. As a final example, the three-element blend “/spr/”, as in the word “spring”, is produced by combining the /s/, /p/, and /r/.