Each speech sound is distinguished by several phonological features. First, the major class features classify segments into consonants, vowels, and glides: [±consonantal], [±vocalic], and [±sonorant] are the three major class features for this purpose.
Consonants are [+consonantal] and vowels are [-consonantal]. The feature [±consonantal] specifically addresses the question of whether there is any major constriction in the vocal tract. It groups together obstruents, nasals, liquids, and glides, which are [+consonantal], versus vowels, which are [-consonantal]. [+consonantal] indicates that sounds are produced with an obstruction or partial obstruction of air in the oral cavity. Note that vowels and glides have no obstruction in the vocal tract, or only a minimal one, compared to that formed by a fricative or a stop.
The feature [±vocalic] makes a further major distinction between consonants and vowels. Vowels and glides are [+vocalic]. The presence of this feature allows us to classify glides independently of both consonants and vowels.
A survey of the classification of the speech sounds by the three major class features appears in Tab. 2.
Tab. 2: Consonants vs. vowels vs. glides
| [consonantal] | [vocalic] | |
| Consonants | + | - |
| Vowels | - | + |
| Glides | + | + |
←33 | 34→
The third major class feature, [±sonorant], is responsible for the distinction between obstruents and sonorants. It characterizes the air pressure in the oral cavity: obstruents are [-sonorant] and sonorants are [+sonorant].
In oral stops, until the obstruction caused by the articulators is released, the air cannot flow through the vocal tract: oral stops are [-sonorant]. In fricatives, even though there is some airflow due to the imperfect obstruction, there is enough constriction for intra-oral air pressure to build up: fricatives are thus also [-sonorant]. In a vowel or glide, on the other hand, the vocal tract is only minimally constricted and air can flow without impedance: vowels and glides are ←34 | 35→[+sonorant]. Nasal consonants have a complete obstruction of airflow through the oral cavity, but nevertheless the nasal passage is open, which allows free flow of air through the nasal cavity. Air pressure does not build up during the production of nasals: nasals are [+sonorant]. In the liquids [l]; and [r], air flows freely over the sides of the tongue: the liquids are [+sonorant] (Tab. 3).
Tab. 3: Major class features for consonants
Turning now to manner features, the feature [±continuant] makes a distinction between stops and fricatives. Stops are [-cont] and fricatives are [+cont]. [+continuant] segments are such that air can flow continuously through the oral cavity. Note that nasals are [-continuant], even though they allow continuous airflow, because the air passes through the nose, not through the mouth. Vowels and glides are [+continuant] (Tab. 4).
Tab. 4: Major class features and [±continuant] for consonants
Consonants are distinguished by the active articulators that produce them. In Fròʔò there are three privative articulator features: [labial], [coronal], and [dorsal].
Labials
The bilabial consonants, [p];, [b], and [m], result from a constriction made by the lips. These consonants are all articulated with a complete oral closure and are thus [-continuant]; see Tab. 5. Labial consonants are distinguished by the contact between active and passive articulators: bilabial or labiodental; see (2) for examples from Fròʔò of labials in word-initial position. The labiodental [f] is a fricative; see (2)b. During its production, the lower lip and the upper teeth come into contact, but no closure takes place. There is no voiced counterpart of the voiceless labiodental fricative [f] in Fròʔò.
Tab. 5: Labials and their features
←35 | 36→
Coronals
There are two groups of coronal consonants distinguished by the feature [±anterior]. Anterior coronals are articulated with the anterior part of the tongue, the corona, which consists of the tip, and the blade of the tongue. Coronals include the alveolar consonants, articulated with the corona against the alveolar ridge.
The primary constriction of the [+anterior] segments is at or in front of the alveolar ridge (either at the lips, the teeth, or just behind the teeth) whereas other coronal consonants, articulated further back in the mouth, are [-anterior]; see the classification in Tab. 6.
There are two coronal stops in Fròʔò: the alveolar voiceless [t]; and the voiced [d]. There is only one sibilant (fricative), the voiceless [s]. Additionally, Fròʔò has a coronal alveolar nasal [n], a lateral [l], an alveolar approximant [j], and an alveolar trill or rhotic [r]. The voiceless and voiced alveolo-palatal sibilants [ʃ] and [ʒ] are absent in Fròʔò, while they are present in other Gur languages such as Nafaran of Supyre and Nafaran of Bondoukou, Kafiire, and Tenere, at least the sound [ʃ] is; see Mensah and Tchagbale (1983). All alveolar segments of Fròʔò appear in Tab. 6 with their respective features. They are attested in the examples in (3) except for [r], which always appears word-internally:
Tab. 6: [+anterior] coronals (alveolars) and their features
←36 | 37→
The second group of coronals are [-anterior]. They are articulated further back in the mouth. The mid part of the tongue is raised against the hard palate. They