Participants and predicates
A predicate describes an event or state and constrains what participants can be expressed. An agent is a typically intentional actor; a causer brings about an event without necessarily acting intentionally; a patient or theme undergoes or is involved in it; an experiencer perceives or feels; a goal is an endpoint; an instrument is used to carry out an action. These labels describe semantic relationships, while subject and object describe grammatical relationships. The subject of a passive clause may be the patient.
Semantic-role labels are analytical conveniences rather than a universal finite inventory built into every grammar. Some verbs fit several analyses, and a participant can have features of more than one role. Ask what the predicate means in the cited construction. Experiencer and causer are semantic roles; surface subject position alone does not identify which participant experiences an event.
The meaning of “with”
Accompaniment and instrument can be distinguished semantically: a companion participates alongside another participant, while an instrument is used in an action. WALS documents that Inga -hua(n) can mark both a companion and an instrument, whereas other languages use different relators. Its cited Inga examples concern arriving with a mayor and measuring with a stick. Those are modern comparative data, not reconstructions of an ancient language.
A case traditionally named “instrumental” need not correspond to English “with” in every construction. A language may use the same marker for a companion, means, cause or other relation, or may divide these among several forms. Begin with the attested predicate, the participant and its marker; only then choose a role label.
Practice
Take one clause from an edited corpus. List each participant in source order, its morphological marking and its semantic relation to the predicate. Rewrite the list after reading a second translation. If the two analyses differ, identify the grammatical or contextual evidence that would decide.
Modern-language examples on this page clarify a linguistic pattern. They do not establish unattested sounds or forms for an ancient language. Follow the cited sources below and keep editorial readings separate from the surviving trace.