Agency
Agency is an aspect of a clause or sentence. Typically, the agent of a clause or sentence is the thing or person that carries out the action told of by the verb. In the sentence, ‘The web designer has done a good job’, the agent is the noun phrase, ‘The web designer’; in a passive form of this sentence, ‘A good job has been done by the web designer’, the ‘web designer’ remains the agent, but now the subject position is filled by what was the object, i.e. ‘a good job’.
The terms agent and subject are different. The former is a semantic label whereas the latter is a grammatical label indicating syntactic position.
