Halliday & Matthiessen (1999: 128-9):
Projecting sequences differentiate rather sharply between figures of sensing and saying on the one hand and figures of doing and being on the other by selecting figures of sensing and saying as the ones that have the special power of setting up other figures as second order, semiotic reality. That is, projecting sequences construe figures of sensing and saying on two levels, the level of sensing/saying itself and the level of the content of sensing/saying. As we put it in Chapter 3, the projecting figure represents symbolic processing, processing that brings another figure into symbolic existence. Figures of symbolic processing involve the symbolic process itself (thinking, saying, etc.) and a participant engaged in the symbolic processing, as in 'Symboliser;' she + Process:' said/thought —> that he had left. The projected symbolic content is either a proposition (she said/thought —> he had left) or a proposal (she asked him —> to leave; she wanted —> him to leave).