A02
core
Scene core
Participant roles
Actor / Source
Who or what starts the event?
basic
Subject
Agent
Causer
意味
The participant that acts, causes, initiates, controls, or is presented as the source of an event.
見分け方
Ask who is doing, causing, or starting the event.
例
単語
I|Peter|the dog|the machine|the wind
フレーズ
the teacher explains|the wind opens
文
The dog bit the postman.
Visual guide
Basic shape
ACTOR / SOURCE who starts the event? [the dog] -> bit -> postman [the wind] -> opens [the teacher] -> explains = doer/causer/source
Compare shape
Actor clues may differ order: [dog] bit postman case: [dog-NOM/ERG] agreement: dog -> verb pronoun form: I / me topic: [dog-TOP] voice: by [dog] role = event starter
言語別ビュー
母語の仕組み
日本語
表れ方
strong
重要度
The actor is often marked by が or introduced as topic with は, but it can be omitted when clear.
犬が走った。
The dog ran.
学習言語では
英語
表れ方
strong
難易度
In basic English clauses, the actor is usually before the verb and can trigger subject-verb agreement.
She opened the door.
she = the actor/source
よくあるつまずき
Learners from flexible word-order languages may move the actor too freely or omit required subjects.
Same block, different coding
Both languages use this block strongly, but they signal it differently. Focus on form changes, not only meaning.