Most good stories start with a fundamental list of ingredients: the initial situation, conflict, complication, climax, suspense, denouement, and conclusion. Great writers sometimes shake up the recipe and add some spice.
Exposition (Initial Situation)
Little Town, It's a Quiet Village...
A quiet, homey scene in a quiet town—a dude riding away mid-day; a woman visiting the man's sister to find out where the guy went. Mrs. Lynde's surprised when Marilla tells her they're planning to adopt an orphan boy, but Marilla's pretty chill about her plan. No problem...so far.
Rising Action (Conflict, Complication)
I'm Just a Girl
The fateful mix-up: Matthew and Marilla get a girl, which, in the late 19th Century, means they can't expect her to help with farm labor. They know they should send her away, but she seems so excited to have a home.
That's the initial conflict, but there are a lot of conflicts afterward. See, instead of a traditional plot structure, this book is episodic, and each episode Anne goes through—the standoff with Gilbert, the trouble with Diana's mother—have their own complications, mini-climaxes, and resolutions. There is one overarching climax, though, which is...
Climax (Crisis, Turning Point)
Not Matthew!
Everything was perfect, which was how we knew something bad was about to happen.
All the players in Anne's life were at her Queen's commencement, cheering her on and proud of her. And when they got back to Green Gables, Anne wished she were a boy so she could help Matthew more with his physical labor, and Matthew told her to remember that he'd rather have her than a dozen boys. Tissue, please.
Matthew dies of a heart attack the next day. More tissues, please?
Falling Action
The Show Must Go On
Anne and Marilla don't even get a chance to grieve. They have to focus on how they're going to keep running the farm.
Anne solves that, and the question of how they'll survive the loss of Matthew, by refusing her scholarship, getting a renter for the farm, bringing in a teaching salary, and living with Marilla. Girl's getting things done.
Resolution (Denouement)
Let's be "Friends"
Anne can definitely hold a grudge. She finally accepts Gilbert's apology for calling her "carrots" several years prior after he gives up his teaching position so she can have it. (What a guy.)
And they stand by Green Gables, talking for a half hour—the promise of a romance to come? The book ends with Anne looking out the window in her room.