a construction defined by the function of modifying a referent with an action concept. Example: I ate the cheesecake [that Carol baked] is an instance of a relative clause construction: that Carol baked is the relative clause (indicated by brackets), the cheesecake is the relative clause head, and I ate the cheesecake is the matrix clause. There are a wide variety of strategies used for relative clauses, including externally headed, internally headed, adjoined, correlative, noun-modifying clause and verb-coding, as well as participles. (Sections 2.2.5, 19.1)