A nasal is a consonant produced with complete closure in the oral cavity (like a plosive) but with the velum (soft palate) lowered, allowing airflow to escape through the nasal cavity. The result is a voiced, resonant sound.
| Phoneme | Place of Articulation | Examples |
|---|---|---|
| /m/ | Bilabial: both lips close | man, hammer, swim |
| /n/ | Alveolar: tongue tip on alveolar ridge | not, winner, sun |
| /ŋ/ | Velar: back of tongue against velum | sing, think, finger |
All three are voiced. They share the same places of articulation as the plosive pairs /p b/, /t d/, /k ɡ/ respectively, so they are homorganic with those plosives.
The velar nasal /ŋ/ has a restricted distribution compared to /m/ and /n/:
A common analysis question: does singer have /ŋɡ/ or just /ŋ/? In most dialects, singer = /sɪŋə/ (no /ɡ/) but finger = /fɪŋɡə/ (with /ɡ/). This is a morphological distinction: sing + -er vs. a monomorphemic word.
The spelling ng represents /ŋ/ word-finally (ring) but /ŋɡ/ word-medially in monomorphemic words (finger, anger, longer as adjective). The spelling nk always represents /ŋk/ (think, bank).
Vowels adjacent to nasals become nasalised: the velum lowers slightly during the vowel, allowing some air through the nose. In English this is allophonic and automatic (not contrastive):
In French and Portuguese, nasalised vowels are phonemic (contrastive), which can cause interference: French speakers may over-nasalise English vowels near nasals.
Nasals are heavily involved in assimilation processes in connected speech, where a nasal changes its place of articulation to match a following consonant:
| Underlying | Assimilated | Example |
|---|---|---|
| /n/ → [m] | Before bilabials | ten balls → [tem bɔːlz] |
| /n/ → [ŋ] | Before velars | ten games → [teŋ ɡeɪmz] |
| /m/ → [n] | Before alveolars (less common) | None listed |
This is one of the most systematic assimilation patterns in English and occurs even in careful speech.
In unstressed syllables, /n/ and /m/ can function as the syllable nucleus (syllabic consonants), replacing the vowel:
These are marked with a subscript vertical line [n̩] in IPA.
Many learners add /ɡ/ or /k/ after /ŋ/ where none belongs:
This is partly an orthographic effect (the spelling ng suggests two sounds) and partly L1 transfer because some languages lack /ŋ/ as an independent phoneme.
Vietnamese has all three nasals /m n ŋ/ and allows them in coda position, so the basic phoneme inventory is not problematic. However:
Some L1s (e.g., Cantonese) have restricted coda nasals. Others (e.g., Japanese) only allow /n/ in coda. Learners may merge final nasals: sin/sing/sim all pronounced the same.