Participant Defined As A Potential Carrier Of An Attribute

Halliday & Matthiessen (1999: 182-3):

We have already set up the general theory of participants, defining them in relation to ascriptive processes of being, being at, and having, in a process-participant configuration. There are three elements in such a configuration: the Process, intensive, possessive or circumstantial; the Attribute, which is being ascribed by one or other of these processes; and the Carrier. It is the role of Carrier which defines the concept of a participant. A participant, according to this theory, is that which may have assigned to it, in the discourse, properties, parts or circumstantial features. For example:

(a) properties (Process of 'being')

some dishes are very tolerant

the grain looks orange and full

a kitchen should be a cheerful place

the swede is more nutritious than the turnip

(b) parts (Process of 'having')

it has branching stems covered with a green succulent flesh

spinach has a decided flavour which some people dislike

they have a pleasant fresh flavour

(c) circumstantial features (Process of 'being at')

this plant is like chicory

these mangoes are from Mexico

the seeds will be inside long coffee-coloured pods

this effect might be because of over-heating

This analysis reveals two important aspects of a participant: 

(i) that it is a thing that can 'carry' or be ascribed attributes, and 

(ii) that the ascription may be of different kinds — intensive (elaborating), possessive (extending), circumstantial (enhancing).