In "The Adventures of Huckleberry Finn," humor is used frequently throughout the novel. One example of this can be found in chapter 21, where Huck is staying with the Grangerfords and the Shepherdsons, two feuding families. When Huck asks Buck Grangerford about the reason for their feud, Buck responds by saying, "Oh, yes, pa knows, I reckon, and some of the other old folks; but they don't know, now, what the row was about in the first place." This absurdity of the feud's origin is a classic example of Twain's use of humor to poke fun at the irrationality of society.
Another example can be found in chapter 16, where Huck convinces Jim that his entire journey down the river has been nothing but a dream. Jim becomes distraught and insists on recounting every detail of their travels to prove that it was all real. This scene highlights the gullibility of Jim, and Huck's mischievous nature in teasing him.
Additionally, the scene in chapter 32, where the Duke and the King perform their absurd Shakespearean play, is another classic example of Twain's use of humor. The Duke and the King's incompetence as actors, combined with their outrageous attempts to add their own twists to Shakespeare's script, make for a hilarious and ridiculous scene.
Overall, Twain's use of humor in "The Adventures of Huckleberry Finn" serves to both entertain and criticize societal norms and customs. Through these humorous moments, Twain is able to expose the absurdity of certain aspects of society and comment on the human condition.