Medium As Indirect Participant

she	was overheard	by the thought police
Range	Process	Medium

Halliday & Matthiessen (2014: 312):

We can make a contrast, then, between direct and indirect participants, using ‘indirect participant’ to refer to the status of a nominal group that is inside a prepositional phrase … the participant rôles of (1) Client, Recipient and Receiver [i.e. Beneficiary] and (2) Scope, Behaviour and Verbiage [i.e. Range] are sometimes expressed ‘indirectly’ in this sense …

Interpersonal 'Between'

Between you and me	the hand-waver and the mentally ill guy	were	talking	absolute rubbish
comment Adjunct: secrecy	Subject	Finite	Predicator	Complement
	Mood		Residue

Non-Spatiotemporal 'Between'

they	drank	all the wine	between them
Actor	Process	Goal	Accompaniment

the contest	is	between British and Iraqi lawn bowlers
Carrier	Process	Attribute: circumstantial: accompaniment

Halliday & Matthiessen (2014: 324):

Accompaniment is a form of joint participation in the process and represents the meanings ‘and’, ‘or’, ‘not’ as circumstantials;