PLOT is what happens. The Protagonist wants something; she can’t get it due to conflicts or hurdles, so she must take action; protagonist wins/loses.
That’s the plot. Of course, the protagonist's desire differs from genre to genre, but the basic plot elements are the same.
Your protagonist is going about her business and something happens to make her stop doing what she has been doing, step out of the comfort zone, and take action. It can’t be something the protagonist can walk away from. It must be central to her dreams, her mission, her very way of life. Remember Shrek, who was content to live in his swamp, but had to leave on a quest? He didn’t really care about the Princess. He just wanted his swamp back. His whole adventure is the plot. Same with Nemo’s Dad.
So the plot has a beginning, a middle, and an end. The beginning is when you set up the stage for the protagonist, tell us who she is, what she does, what she wants, what’s important to her. The end of the beginning is when something happens that upsets her way of life. (Simba has to run away from Pride Rock). End of part I.
The middle is when she does things to fix the problem. This is the longest part of the novel. The problem can be the antagonist, who can be a person (the villain), or an organization (evil company), a situation (protagonist loses her job or family member dies), nature (tsunami, volcano), anything that makes her do something. Each conflict is tougher and more dangerous, threatening her wellbeing. The end of the middle is when nothing seems to be working, and the protagonist is most likely to fail, and something or someone helps her out.
The end is when everything is resolved. Protagonist faces the greatest hurdle; she must vanquish the enemy and finally, either wins after the epic battle (saves the world or gets the promotion) or loses, but gains something else in return (loses job but realizes that life is more than just that, relationships get fixed).
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