A characteristic that is shared by good fantasy writing and by good satire (or found in a work that is both) is careful attention to descriptive detail. Identify at least two specific examples of such careful attention in Gulliver's Travels, Part 4, and explain how they help develop our responses to the story.
On the topic of detailed description, I have two observations. One is that at times Swift is as general in his descriptive passages (e.g., the opening paragraph of Part IV) as he is at other times detailed (e.g., the fourth paragraph of Part IV). The other is that--really--at times Swift takes detailed description to the point of absurdity.
Their heads and breasts were covered with a thick hair, some frizzled, and others lank; they had beards like goats, and a long ridge of hair down their backs, and the fore parts of their legs and feet; but the rest of their bodies was bare, so that I might see their skins, which were of a brown buff colour. ...
The descriptions of the beasts, the beginning of which is excerpted above, is one example of detailed descriptive writing, but I would quarrel with the assertion that it is therefore "good" writing. The response elicited--and that which Swift intended--is one of disgust, which is a response (satire or no) that might drive a good many readers away rather than forward in the story.
I have to agree that the story's descriptive details offer a view to its readers which is meant to be satirical. Swift's use of detail and imagery can awaken in engaged readers a poignant view of the world around them. Sometimes it takes us stepping outside of our comfort zone to realize what is wrong within our own lives, societies, and cultures.
Therefore, as vangoghfan points out, Gulliver's descriptions of both war and corruption is important.
Yes, one way of approaching this question would be to look at the way in which Gulliver describes the various social and legal systems of the worlds that he visits in great detail. Of course, Swift does this to satirise various beliefs, values and institutions of his time and day, and an excellent example would be Gulliver's explanation of why humans fight battles.
Several good examples of such detail can be found in Chapters 5-7 of Part IV. One of these would include Gulliver's descriptions of the reasons humans go to war. Another would include Gulliver's descriptions of the corruptions of the English legal system. Finally, one more example would include Gulliver's description of the flaws and failings of young English aristocrats.