I agree with Berardinelli.

The wording in the instructions of Reading Like A Writer is confusing to me, so I will do my best.
Comparisons that Berardinelli used in the second paragraph:
Avatar vs. Dances with Wolves- narrative and scifi
Avatar vs. Aliens- Space/military
Avatar vs. Titanic- Romance
Berardinelli  classifies Avatar as all of the above. It is not just a single one of them because it has aspects from the scifi in the fancy new Na'vi world and the space/military because Jake Sully is a military man and the bad guys are all working for the military, but there is romance with Jake and Neytiri. All of that packed into one wonderful movie means that it could not possibly fall into a single category. Even the poster would suggest that.

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