In
linguistics, a grammatical agent is the
participant of a situation that carries out the
action in this situation. Also, agent is the name of the
thematic role (also known as the
thematic relation) with the above definition. The word comes from a participle of the Latin verb agere, to do.Typically, the situation is denoted by a
sentence, the action by a
verb in the sentence, and the agent by a
noun phrase.For example, in the sentence "Jack kicked the ball", Jack is the agent. In certain languages, the agent is
declined or otherwise marked to indicate its grammatical role. In
Japanese, for instance, the agent is typically affixed with |ga| (the
hiragana が). Although
Modern English does not mark grammatical role, agency is informally represented using certain conventions; for instance, with the
morphemes "-ing", "-er", or "-or", as in "eating", "user", or "prosecutor". (Cf.
agent noun.)
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