So much of the writing we read is written by amateur writers who are professionals in some other realm.
I should probably offer suggestions, which is hard; but try this recent nonfiction essay by novelist & essayist Hilary Mantel:
Or read the first few pages of The End by Salvatore Scibona (click "look inside the book" on Amazon):
These are both fiction-writers; I'm struggling to think of really high-quality non-fiction writing, but that's just because I haven't read any recently... An example, at least -- Christopher Hitchens covers some of the same territory as Richard Dawkins, but his writing is head & shoulders above.
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