Syllabification is a controversial topic in linguistics. There isn't a 'standard' way of syllabifying words, but there's a phonological rule called Maximal Onset Principle (MOP), according to which intervocalic consonants should be syllabified as the onset of the following syllable as long as the Phonotactic constraints allow it. This would mean that VCV has to be syllabified as V.CV as long as the onset of the second syllable is permissible. There are exceptions, however.
I will mark ill-formed sequences of sounds with a preceding asterisk.
So banana should be syllabified as:
- /bə.ˈnɑː.nə/, not */bən.ˈɑːn.ə/ or */bə.nɑːn.ə/
The first /-n-/ is intervocalic, so it should be the onset of the second syllable and it is a permissible onset (there are so many words that start with /n/ such as night, name, noon etc.). The same goes for the second /-n-/.
Obsessive is syllabified as:
- /əb.sɛs.ɪv/, not */ə.bsɛs.ɪv/ or */əb.sɛ.sɪv/
Although the consonant cluster /-bs-/ is intervocalic, it's not syllabified as the onset of the next syllable because it violates the Phonotactics of English. And the reason as to why the second syllable is /sɛs/ and not */sɛ/ is that there's no English word that ends with the lax vowel /ɛ/ (except meh). The syllabification given in the dictionary is correct.
Extreme is syllabified as:
- /ɛk.ˈstriːm/ not */ɛks.triːm/ or */ɛ.kstriːm/
According to MOP, the intervocalic consonants /-kstr-/ should be syllabified as the onset of the next syllable; however, if we syllabify it as */ɛ.kstriːm/, it violates the Phonotactics of English because English cannot have an onset starting with PLOSIVE + FRICATIVE, so the /k/ becomes the coda of the first syllable, /ɛk/. /str-/ conforms to the phonotactic rules of onset clusters, so it becomes the onset of the next syllable, /striːm/.
There's another theory (or an exception to MOP) that states that stressed syllables having lax vowels such as /ʌ ɪ ʊ ɛ/ should not have an empty coda, so obsessive should be /əb.ˈsɛs.ɪv/, very should be /ˈvɛr.i/, city should be /ˈsɪt.i/ etc. Banana is pronounced with a lax vowel /æ/ in American English, in which case, it's syllabified as /bə.ˈnæn.ə/ (or /bəˈnæn.nə/, according to the ambisyllabicity theory).
Yet another theory says that the consonant following the lax vowels /ʌ ɪ ʊ ɛ/ should be ambisyllabic. 'Ambisyllabic' means that it it belongs to both the preceding and the following syllable. So according to the ambisyllabicity theory, obsessive can be syllabified as:
'Intervocalic' means between vowels e.g. the /t/ in city, better, water etc., is between two vowels, so it's intervocalic.
Typically, a syllable consists of three segments; onset, nucleus, coda. The word bat /bæt/ can be analysed as: /b/ → onset, /æ/ → nucleus, /t/ → coda.
- onset: it refers to the consonant(s) before the nucleus (usually a vowel)
- nucleus: a vowel/diphthong or a syllabic consonant that forms the syllable peak
- coda: consonant(s) after the nucleus
Phonotactic constraints are language-specific rules that determine the permissble sequences of sounds. For example, Greek allows word-initial /pn-/ as in pneumonia, but English doesn't, that's why the /p/ is dropped in pneumonia in English.
V → vowel, C → consonant