is necessary to apply a rule that changes to before or , then a second rule that deletes when it follows . 1. → / velar consonant 2. → ∅ / _ These produce the following results: However, these rules do not predict the following phonetic forms: In the above cases, the is not deleted. The words are all single morphemes, unlike singer and singing which are composed of two morphemes, sing plus -er or -ing. Rule 2 can be amended to include a symbol # for a morpheme boundary (including word boundary): 2. /ɡ/ → ∅ / [ŋ] ___ # This rule then applies to sing, singer and singing but not to anger, finger, or hunger. According to this rule, the words hangar ('shed for aircraft'), which contains no internal morpheme boundary, and hanger ('object for hanging clothes'), which comprises two morphemes, are expected to constitute a minimal pair as hangar versus hanger ; in actuality, their pronunciations are not consistently distinguished in this manner, as hangar is frequently pronounced . Additionally, there are exceptions in the form of comparative and superlative forms of adjectives, where Rule 2 must be prevented from applying. The ending -ish is another possible exception. As a result, there is, in theory, a minimal pair consisting of longer ( 'more long') and longer ( 'person who longs'), though it is doubtful that native speakers make this distinction regularly. Names of persons and places, and loanwords, are less predictable. Singapore may be pronounced with or without ; bungalow usually has ; and Inge may or may not have . Vowel system It is often stated that English has a particularly large number of vowel phonemes and that there are 20 vowel phonemes in Received Pronunciation, 14–16 in General American, and 20–21 in Australian English. These numbers, however, reflect just one of many possible phonological analyses. A number of "biphonemic" analyses have proposed that English has a basic set of short (sometimes called "simple" or "checked") vowels, each of which can be shown to be a phoneme and which can be combined with another phoneme to form long vowels and diphthongs. One of these biphonemic analyses asserts that diphthongs and long vowels may be interpreted as comprising a short vowel linked to a consonant. The fullest exposition of this approach is found in , where all long vowels and diphthongs ("complex nuclei") are made up of