Short lexical | The boy is hugging the girl | Different action (e.g., pulling) | Can be decided based on lexical information alone |
Short active | The girl is kissing the boy | Agent and patient reversed | Relatively straightforward, since sentence conforms to language-general word order principles |
Short passive (noncanonical) | The boy is kicked by the girl | Agent and patient reversed | Noncanonical word order (patient is initial and agent is in prepositional phrase), so requires attention to passive morphosyntax |
Long lexical | The girl who is green is pushing the boy | Different action (e.g., chasing) | Can be decided based on lexical information alone |
| The boy is kissing the girl who is red | Different-colored patient (e.g., green girl) | Can be decided based on lexical information alone |
Long easy | The girl is pulling the boy who is red | Color is assigned to wrong participant (e.g., red girl) | Relatively straightforward, since correct head noun for relative clause is in canonical position immediately to the left of the relative |
| The boy who is red is chasing the girl | Agent and patient reversed | Relatively straightforward, since sentence conforms to language-general word order principles |
Long medium (Noncanonical) | The girl who is washed by the boy is green | Color is assigned to wrong participant (e.g., green boy) | Passive relative clause separates adjective from the noun it modifies; attention to hierarchical structure is required to assign the adjective to the matrix subject, not the adjacent noun |
| The girl who the boy is hugging is red | Agent and patient reversed | Object relative clause results in noncanonical word order (the agent follows the patient), so requires attention to the syntax of the relative clause |
Long hard (Noncanonical) | The boy who the girl is pushed by is blue | Agent and patient reversed | Highly infrequent adjunct relative passive clause make assignment of thematic roles very difficult |
| The girl who the boy is kissed by is green | Color is assigned to wrong participant (e.g., green boy) | Passive adjunct relative clause separates adjective from the noun it modifies; attention to hierarchical structure is required to assign the adjective to the matrix subject, not the closer noun |