Sentence:  While the phonemes can be very easily stated , no one is likely to be satisfied with the statement until phonemic occurrences can be related in some way to morphemic units , i. e. until the <WSD>morphophonemics</WSD> is worked out , or at least far enough that it seems reasonable to expect success . 
Meaning of the word marked with <WSD> tags:  the study of the phonological realization of the allomorphs of the morphemes of a language