Answer:
The Ngbandi tone change that marks a plural subject is a different matter. The
concatenation analysis is not only clumsy and counterintuitive (the morphology is NOT
things in a string, like a root plus a suffix), it does not say what we want to say. As
stated, it makes the stem with the tone change look like an allomorph of the stem without
the tone change. What we would really like to say, however, is that the tone change is
something ADDED to the stem. The generative formalism of suprasegmental phonology
gives a way to do this. This formalism takes suprasegmental phenomena-in particular
tone, stress, intonation-as being separable from the segments (consonants and vowels)
that they are attached to.
Here are examples showing how we can adapt the suprasegmental formalism