In the last chapter we saw how languages use grammatical morphology to create a very abstract kind of semantics, dividing the things, attributes, and situations that language is about into a small number of general categories. But grammatical morphology has another function, derivation, the creation of new words designating new concepts that are related to the meanings of existing lexical morphemes. Because this process is often generally applicable to whole categories of lexical morphemes, it is a good example of the productivity of language. Given a new adjective zug to designate some new attribute, an English speaker can create unzugto mean the attribute on the opposite end of some dimension from that attribute and zugness to mean the condition of having that attribute. As with the inflectional morphology described in the last chapter, languages also differ considerably in what possibilities they offer speakers for creating new words and new meanings using morphology. These differences lead to quite different ways of expressing similar meanings in different languages. In fact some languages may permit construals that are awkward or impossible in other languages.
One particular area of grammar where these differences are apparent is in the way the participants in events are represented in noun phrases in sentences. Many languages have productive verb morphology that allows particular participants to be foregrounded or backgrounded, giving these languages an unusual flexibility in this part of their grammar. In this chapter we'll examine this sort of flexibility in Lingala.