【正确答案】正确答案：A semantic role refers to the underlying relationship that a participant has with the main verb in a clause.(1 point)More often than not, noun phrases are arguments of verbs. These arguments may serve various semantic roles: the agent of an action, the patient and other roles such as the instrument or the goal. The agent is the participant who is in control of an event, the patient is the participant who is affected by an event,and the instrument is the inanimate identity related to the main verb in the sentence.(2 point)In the sentence " The young man knocked the door open with a brick" and its passive version" The door was knocked open by a young man with a brick" ,"the door"plays the role of the patient, "a young man"is the agent and "a brick" is the instrument. The difference lies in the position of semantic roles. The sentence with"the door" as its subject emphasizes the condition of the door, while the passive voice attaches great importance to"the young man"and tries to describe what the young man did.(2 points)

【答案解析】解析：考查语义角色。语义角色是指语言成分在句子所表达的事件中所扮演的参与者角色。从某种意义上说，语义角色是语言学家对句子结构成分之间意义关系的一种分类。语义角色包括施事(agent)、受事(patient)及工具(instrument)等。其中施事指有生命的动作发出者，受事指被句中动作或状态所影响的事物，工具指动作或状态牵涉到的无生命的力量或客体。语义角色在主动句和被动句中所处的位置可能不同，由此导致两种句型所强调的内容不同。