The term grammatical functions refers to syntactic categories, primarily subjects, objects, and adjuncts. They relate a verb to its dependents syntactically. Grammatical functions are not to be confused with semantic categories like agent or patient. Overall, there is a systematic relationship between these syntactic and semantic categories that can be described as follows: if a verb takes an agent and a patient argument, the agent will always be expressed as the subject and the patient as the object (in an active clause). However, this is not a one-to-one relationship; while agents are always subjects, subjects can bear a number of different thematic roles including experiencer, recipient, or even patient.