Phonetics (Basic Terms for English Vowels)

Articulatory Properties of Vowels

Because vowels are produced with a relatively open vocal tract, they do not have a consonant-like place or manner of articulation (constriction). They are also almost always voiced. This means that the three standard descriptors for consonants (place, manner, and voicing) are not helpful when we want to describe vowels. What should we use instead? * Height (high, mid, low): raising or lowering the body of the tongue. * Backness (front, central, back): advancing or retracting the body of the tongue. * Rounded: rounding or not rounding the lips. * Lax or Tense: making these movements with tense or lax gestures.

Tongue Advancement (Backness: front, central, back)

Besides being held high or mid or low, the tongue can also be moved forward or pulled back within the oral cavity. For example, in the high front vowel [i] as in beat, the body of the tongue is raised and pushed forward so it is just under the hard palate. The high back vowel [u] of boot, on the other hand, is made by raising the body of the tongue in the back of the mouth, toward the velum. The tongue is advanced or moved forward for all the front monophthongs, [i], [ɪ], [ɛ], [æ], as in seek, sick, sec, sack, and retracted or pulled back for the back monophthongs, [u], [ʊ], [ɔ], [ɑ], as in ooze, look, draw, dot. The central vowels, [ᴧ] as in luck or [ə] as the first vowel in the word another, require neither advancement nor retraction of the tongue.

Describing Vowels: Diphthongs

Complex vowel sounds, as opposed to monophthongs, which are simple vowel sounds. They are "complex" because they are two-part sounds, consisting of a transition from one vowel to the other in the same syllable. The diphthong in buy, which consists of two articulations and two corresponding vowel sounds, is thus written as a two-part symbol: [ɑɪ] as in buy [bɑɪ].6 Although a diphthong consists of a sequence of sounds, it is considered one sound, similar to an affricate. If you try saying the word eye slowly, concentrating on how you make this vowel sound, you should find that your tongue starts out in the low back position for [ɑ]7 and then moves toward the high front position for [ɪ] (see (4)). If you have a hard time perceiving this as two sounds, try laying a finger on your tongue and saying eye. This should help you feel the upward tongue movement. To produce the vowel in the word bow (down), the tongue starts in the low back position for [ɑ] and moves toward the high back position for [ʊ] while the lips round, so this diphthong is written [ɑʊ], as in [bɑʊ]. In the vowel of the word boy, the tongue moves from the mid back position for the rounded vowel [ɔ] toward the high front position for [ɪ]; so the diphthong of boy is written [ɔɪ], as in [bɔɪ]. To say the vowel in the word bow (and arrow), the tongue starts in the mid back position for the rounded vowel [o] and moves toward the high back position for the rounded vowel [ʊ]; so the diphthong is written [oʊ], as in [boʊ].For the production of the vowel of the word bay, the tongue starts in the mid front position for [e] and moves toward the position for [ɪ]; so this diphthong is written [eɪ], as in [beɪ] bay. The chart in (4) illustrates the tongue movements involved in the production of these diphthongs.

We can use these four characteristics to create the descriptions of English vowels.

Sample descriptions of English vowels a.[i], as in beat, is high, front, unrounded, and tense. b.[ɔ], as in caught or thaw, is mid, back, rounded, and lax. c.[ɑ], as in cot, is low, back, unrounded, and lax. d.[ᴧ], as in cut, is mid, central, unrounded, and lax. (Note that "central" and "mid" refer to the same general area in the vocal tract but along different dimensions.)

Tongue Height (height: front, mid, low)

The first two of these aspects have to do with the position of the tongue in the mouth. The highest point of the tongue body is considered to be the place of the vowel, as you can see by comparing the tongue position in with the placement of the symbols in. These varying degrees of openness correspond to different degrees of tongue height: high for [i], mid for [ɛ], and low for [æ]. High vowels like [i] are made with the front of the mouth less open because the tongue body is raised, or high. The high vowels of English are [i], [ɪ], [u], and [ʊ], as in leak, lick, Luke, look, respectively. Conversely, low vowels like the [æ] in sat are pronounced with the front of the mouth open and the tongue lowered. The low vowels of English are [æ] as in cat and [ɑ] as in cot. Mid vowels like the [ɛ] of set are produced with an intermediate tongue height.2 In the inventory of English monophthongs, these mid vowels are [ɛ, ᴧ, ɔ], as in bet, but, bought, respectively. Note that an unstressed vowel in English is often pronounced as the mid vowel [ə], as in above and atomic. In many American dialects, words like caught and cot, or dawn and Don, are pronounced differently, with an [ɔ] and [ɑ], respectively. In other American dialects, these words are pronounced the same. If you pronounce these pairs the same, you probably use the unrounded vowel [ɑ] in all of these words. For most speakers of English, however, even those who pronounce caught and cot the same, the vowel [ɔ] appears in words such as law and saw, as well as in words like core and more.

Lip Rounding

Vowel quality also depends on lip position. When you say the [u] in two, your lips are rounded. For the [i] in tea, they are unrounded, or spread. English has three rounded monophthongs: [u], [ʊ], [ɔ], as in loop, foot, paw; all other monophthongs in English are unrounded. In the vowel chart in, the rounded vowels are enclosed by the dashed line.

Vowel Monophthongs v.s. Diphthongs

Vowels in turn are often divided into two categories: monophthongs ([mɑnəpθɑŋz]) and diphthongs ([dɪfθɑŋz] or [dɪpθɑŋz]). You can think of monophthongs as simple vowels, composed of a single configuration of the vocal tract, while diphthongs are complex vowels, composed of a sequence of two different configurations. We consider diphthongs to be "single" vowels, however, because the sequence of two configurations acts as the nucleus to a single syllable. To conceptualize this better, think of the two words knives and naive. The actual vowel sounds in these two words are essentially the same, but in knives, there is just one syllable nucleus (the diphthong [ɑɪ]), while in naive, there are two separate syllables with two separate nuclei (the monophthong [ɑ] in the first syllable, followed by the monophthong [i] in the second syllable).

Tenseness (Lax and Tense)

Vowels that are called tense are said to have more extreme positions of the tongue and/or the lips than vowels that are lax. The production of tense vowels involves bigger changes from a mid-central position in the mouth. That is, they require a more extreme tongue gesture of raising, lowering, advancing, or retracting in order to reach the periphery (outer edges) of the possible vowel space. This means that the tongue position for the tense high front vowel [i] is higher and fronter than for the lax high front vowel [ɪ]. Lax vowels, then, are not peripheral to the degree that tense vowels are. Compare tense [i] in meet with lax [ɪ] in mitt, or tense [u] in boot with lax [ʊ] in put. In the latter case you will find that the tense rounded vowel [u] is also produced with more and tighter lip rounding than the lax counterpart [ʊ]. In the vowel chart in (1), you can clearly see that the distance between the tense vowels [i] and [u] is bigger than the distance between the lax vowels [ɪ] and [ʊ]. Additionally, tense vowels in English usually have a longer duration (in milliseconds) than lax vowels.