Halliday & Matthiessen (1999: 168):
Like other participants Range is realised grammatically by a nominal group, but it does not participate in the process operationally: it does not bring about or act out the process, nor is it affected by it materially or mentally. It specifies the domain over which the process is actualised. For instance, if a process of walking ranges over Manhattan, it can be represented as Process + Range: They walked the streets of Manhattan. There are three respects in which the Range is not a prototypical participant:(I) its relationship to the Process,(II) its degree of individuation,III) its interpersonal potential.