Halliday & Matthiessen (1999: 155):
Of all the participants, the Medium is the most restricted in terms of the range of phenomena that may function in that role. We can see this in relation to the general types of figure:
We can also see this in relation to more delicately specified subtypes such as:
In other words, whatever the type of figure, the participant that is most closely bonded with the Process is the one that takes on the generalised role of Medium; it is this that is in a relation of mutual expectancy with the Process. This is not to say that only horses can neigh, but rather than anything that neighs is thereby endowed with horse-hood.
Blogger Comments:
Clearly, the Medium of a 'shine' figure is not limited to 'heavenly body', but includes artificial light sources and phenomena with reflective surfaces, such as black shoes.