The GA consonant phonemes have many different allophones. As you know, allophones of a phoneme are specific to a particular phonological context. A phonological context is given by either or both of the following two types of information:
Information of the first kind is easy enough to state. For example, we can say that when GA /t/ precedes GA /θ,ð/, it will be dental. Information of the second kind can only be given if we agree on what the syllable structure of GA words is. But while it is intuitively clear how many syllables any given word has, it is not intuitively clear where, in a string of consonants, one syllable ends and another begins. The word extra has two syllables, but are they /ɛ/ and /kstrə/, /ɛk/ and /strə/ or /ɛks/ and /trə/, /ɛkst/ and /rə/, or /ɛkstr/ and /ə/? Since the realizations of GA consonants frequently crucially depend on whether they occur at the beginning or end of a syllable, we need to deal with the question how GA words are syllabified.