Page 9 of the 2017 Scrum Guide says "Sprints contain and consist of the Sprint Planning, Daily Scrums, the development work, the
Sprint Review, and the Sprint Retrospective."
So each Sprint is comprised of one cycle of all those events.
However, page 11, when discussing what is accomplished during Sprint Planning, says "...enough work is planned during Sprint Planning for the Development
Team to forecast what it believes it can do in the upcoming Sprint."