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Read Ender's Game by Orson Scott Card
How does Ender use his desk (tablet/laptop) to make fun of Bernard?
Answer:
Ender used his desk to send a message to his classmates making fun of Bernard without being discovered in retaliation for making fun of Shen.
Step-by-step explanation:
Since Bernard had been comparing Shen to a warm, making a connection between the warms anatomy and Shen´s walking style, Ender sent messages referencing the same idea but focusing on how weird Bernard´s fixation on his classmates´ bodies was. He was able to send the messages through a nonexistent student´s file to avoid being discovered.