(By Bernard Comrie): "The core argument of a canonical, one-place intransitive predicate may be symbolized S. The two core arguments of a canonical, two-place transitive predicate may be symbolized as A and P, with A representing the more agent-like argument and P the more patient-like (Comrie 1978). (In another terminology, the symbol O is used rather than P; Dixon 1994.) In studying the alignment of case marking, we ask the question which of S, A, and P are coded identically and which are coded differently. Note that for the purposes of this chapter, only case marking is considered. Alignment of person marking in the verb is treated in Chapter 100. Other manifestations of alignment are also possible, such as word order, but are not treated here."