Occur instantaneously and usually mark the beginning or the end of an action.

An interleaved sequence of events and actions.

They represent actions and operations in the domain.

The "things" (whether concrete or abstract) in the domain.

During sprint planning the backlog items are chosen from the product backlog and placed on the sprint backlog.

The product backlog is the outcome of a development project.

Missing feature descriptions are first entered in the sprint backlog and at the end of a sprint they are transferred to the product backlog.

DRNA officer: person employed by DRNA, responsible for monitoring environmental resources, enforcing compliant use of resources, document and report violations of rules, ...

beach resident: a person who lives in a building adjacent to a beach

DRNA management: person(s) who are in charge of overseeing the work of some DRNA personnel, to provide them means of conducting that work, to assign work to them, ...

swimmer: a person located in the water, not supported by the ground, and moving her/his body in order to propel their body through water