Manners of articulation

The manner of articulation of a sound is the degree and the kind of obstruction of a consonant in the vocal tract. For example, if we compare the first sounds of the words tip and sip, we realize that the airflow is obstructed in the same area (alveolar), and in both sounds, /t/ and /s/, the configuration of the vocal cords is the same (voiceless). The difference between the two sounds lies in the type of obstruction of the airflow. While in /t/ we stop the air completely before the release, we simply obstruct (not stop) the airflow with a narrowing created by the articulators in /s/.

Stop: A stop consonant involves a complete closure of the articulators and thus total blockage of airflow. The stops found in English are /p, b, t, d, k, g/.

Fricative: A fricative is a sound that is made with a small opening between the articulators, allowing the air to escape with audible friction. In English /f, v, θ, ð, s, z, ʃ, Ʒ, h/ are the fricative sounds. The common denominator of fricatives is partial airflow with friction noise. Some manuals, adhering strictly to the requirement of turbulent airstream, do not consider /h/ a fricative. A subgroup of fricatives (alveolars and palato-alveolars), which are more intense and have greater amounts of acoustic energy at higher frequencies, are known as ‘sibilants’.

Affricate: In a stop sound, the release of the closure is quick and abrupt; however, in sounds where the closure release is gradual, it creates friction. Such sounds are called affricates. In other words, affricates start like stops (complete closure), and end like fricatives. Both affricates of English, /ʧ, ʤ/, are produced in the palato-alveolar place of articulation. The symbols used for these sounds reveal the combination of stops /t/, /d/ with the fricatives / ʃ /, / Ʒ /, respectively. An important point to remember is their one-unit (inseparable) status. Unlike consonant clusters (e.g. /sk/, /pl/), which are made up of two separable phonological units, affricates always behave like one unit. For example, in a speech error such as key chain [ki ʧ en] becoming [ʧi ken], the affricate /ʧ/ is interchanged with a single segment /k/; clusters, on the other hand, are separated in a comparable situation, as illustrated in scotch tape [skΛʧ tep] becoming [kΛʧ step] and not [tΛʧ skep]. Since affricates /ʧ/ and /ʤ/ contain sibilant fricatives in them (/ʃ /, / Ʒ /, respectively), they are also sibilants. Stops, fricatives, and affricates, which are produced by a considerable amount of obstruction of the laryngeal airstream in the vocal tract, are collectively known as ‘obstruents’.

Approximant: Approximants are consonants with a greater opening in the vocal tract than fricatives, and thus do not create any friction. Identifying a sound as an approximant or a fricative includes acoustic/auditory and aerodynamic considerations as well as articulatory factors. Catford (1977) states that the typical cross-sectional area of the maximum constriction in a fricative ranges from about 3 to 20 mm², while it is greater than 20 mm² in an approximant. The sounds /l, ɹ̣, j, w/ (the initial consonants of lay, ray, yes, and week) are the approximants of English. Both fricatives and approximants, because they let the airflow continue in the production, are called ‘continuants’. Two of the English approximants, /l, ɹ̣/, are ‘liquids’, vowel-like consonants in which voicing energy passes through a vocal tract with a constriction greater than that of vowels. The liquid /l/, which is called the ‘lateral’ liquid, is produced with the tongue tip creating a closure with the alveolar ridge while maintaining an opening at the sides of the tongue where the air escapes. The non-lateral approximant, /ɹ̣/, which was described earlier in relation to retroflex place of articulation and is also known as the ‘rhotic’, will not be repeated here.

The remaining two approximants, /j/ and /w/, are known as ‘glides’ (also ‘semi-vowels’ in some manuals). These are vowel-like sounds that function like consonants. In other words, /j/ is like the vowel /i/ and /w/ is like the vowel /u/ in production, while functioning like consonants, as they do not occupy the syllable nuclei and they always need a vowel to lean on.

Nasal: If we compare the initial sounds of beat and meat, /b/ and /m/, we see that they share the same place of articulation (bilabial) and voicing (voiced). The difference between them lies in the velopharyngeal opening and the channels of the outgoing airflow. In the production of /m/, the velum is lowered and the velopharyngeal passage is open. Thus, upon release of the closure, the air goes out through the nasal cavity as well as through the oral cavity. In the production of /b/, on the other hand, the velum is raised and the passage is closed. Consequently, the only outlet for the airflow is the oral cavity. Sounds that are made with the former configuration, e.g. /m, n, ŋ/, are called nasals; the others are oral sounds.

Approximants (liquids and glides) and nasals, because they include a relatively unobstructed flow of air between the articulator and the place of articulation, collectively form the group of consonants that is known as ‘sonorants’.

Table 1 shows the places and manners of articulation for English consonants. Whenever a cell has two consonants, the voiceless one is placed to the left and the voiced one to the right.