As the name suggests, the main characteristic of a nasal consonant is that when it is produced the air escapes through nose.
The air passes through the nose because of a complete closure in the mouth. There are three types of closure: bilabial (lips), alveolar (tongue blade against alveolar ridge), and velar (back of tongue against soft plate).
These three types of closure produce three nasal consonants. They are: m, n, and ŋ. These 3 nasal consonants correspond to the three places of articulation for the pairs of plosives p-b, t-d, and k-g.
The nasal consonants m and n are simple and there is very little to describe. However, the nasal consonant ŋ is the one that creates some problems for learners of English and it is analysed in details below.
The nasal consonant ŋ is a sound that gives considerable problems to foreign learners. It is unusual in its phonological aspects and some people consider that it should not be one of the phonemes of English language.
Let’s take a look at the ways in which the distribution of ŋ is unusual.
In initial position the nasal ŋ never occurs. It is the only consonant in English language that can not occur in initial position (maybe ʒ is another exception).
The nasal consonant ŋ occurs frequently in median position. The question that appears when ŋ occurs in median position is whether it should be pronounce with a following plosive or without one. When ŋ is followed by the letter k, the k sound is always pronounced. However, when ŋ is followed by the letter g, sometimes the g sound is pronounced, sometimes it is not pronounced. Let’s take a look at the following examples:
The ŋ is followed by the g sound
Finger /ˈfɪŋ gər/
Anger /ˈæŋ gər/
The ŋ is NOT followed by the g sound
Singer /ˈsɪŋ ər/
Hanger /ˈhæŋ ər/
Quite strange I will say! Why in the case of the pronunciation of the words "finger" and "anger" the /ŋ/ is followed by /g/ and in the case of the pronunciation of "singer" and "hanger" it is not?
If we take a closer look at the words "singer" and "hanger" (the ones that /g/ sound does not occur in their pronunciation) we can see that they are made of two morphemes: "sing" + "-er" and "hang" + "-er". The words "finger" and "anger" consist of just one morpheme.
So, in the case when /ŋ/ occurs at the end of a morpheme (singer = /ˈsɪŋ ər/) it is not followed by the sound /g/ (the word singer is formed by two morphemes: "sing" and "er". The /ŋ/ sound is found at the end of the morpheme "sing". As a result, the /g/ sound is not found in the pronunciation of the word "singer").
In the case when /ŋ/ occurs in the middle of a morpheme, the /g/ sound always follows the /ŋ/ sound as in the case of the word "finger".
The rule – Within a word containing the letters "ng" in the spelling, /ŋ/ occurs without a following /g/ if it occurs at the end of a morpheme. If it occurs in the middle of a morpheme it has a following /g/.
Another special situation in which /ŋ/ is followed by /g/ is the comparative and superlative suffixes.
According to the above rule, the word "long" should be pronounced /lɔŋ/ (which is correct). That means, if we add another morpheme to the word "long", such as the suffix "-ish", the pronunciation of the resulted word will also be without the /g/ sound (which is also correct). Rationally, we will be tempted to believe that the comparative and superlative forms of the word long would be pronounced with no /g/ sound following the /ŋ/. In fact, this is not true. In the case of the superlatives and comparatives, the /ŋ/ is followed by the /g/ sound.
Longish /ˈlɔŋ ɪʃ/
Longer /ˈlɔŋ gər/
Longest /ˈlɔŋ gɪst/
In conclusion, the superlatives and comparatives forms of adjectives must be considered single-morpheme words for the purpose of the rule.
Another interesting thing about the /ŋ/ is that there are only five vowels it follows. These vowels are: ɪ, e, æ, ʌ, and ɒ.
The nasal /ŋ/ never occurs after a diphthong or a long vowel.
The consonant /ŋ/ is phonetically simple but phonologically complex. Phonetically, it is simple because it is no more difficult to produce than /n/ or /m/. Phonologically difficult, because it is not easy to describe the context in which it occurs.