2. what are some rules for an effective book review?

Explanation:

The way I handle a book review that has a plot is to mention very briefly the main part of the plot detailing only what is absolutely necessary to show the conflict.

For example, every decade | read War and Peace. Here's what I would say about the main plot.

The main plot shows the struggle Pierre goes though when he stays in Moscow as Napoleon enters. He has the idea that he will assassinate Napoleon. His plan is thwarted by a soldier who captures him and puts him with the other Russian prisoners who remained behind in Moscow. What follows is the events making up the retreat which are horrible in their details.  And Pierre, an aristocrat, sees things not even the peasants he is with could begin to imagine. War and Peace is so long and so extensive that even this could be considered a sub plot.

War and Peace is some 1200 pages long (or more -- depending on the edition), so I would work on some of the subplots. For example, how did Natasha go from being the bell of the ball to an overweight dull middle age frump  who seemed settled in her life, but totally uninteresting? How did Andre's death affect her when she was a very young girl and called upon to do nursing duty when she hardly understood the nature of his wounds and that he would eventually die? Sub plots are full of things that you can expand without giving away the main plot.

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