Halliday & Matthiessen (1999: 158, 159, 160):
A good place to illustrate the complementarity of the two models of participation is in the area of doing and being. Here the two models also bring out the complementarity of doing and being as modes of construing a quantum of change in the flow of events. …Figure 4-12 brings the two models together to show (i) how they complement one another, the generalised one showing how doing and being are based on the same configuration of Agent + Medium + Range and the particularistic one showing how doing and being are different configurations of roles; and (ii) how doing and being serve as complementary perspectives on a quantum of change, construing it either as happening/coming into being or as outcome of happening/ being. …
