Reading gives me new nuggets of English language, like tiny seeds that can help me explain the most primitive, most repetitive scenes (it drives me nuts when I can't come up with an alternative).
For example, I used to not know how else to call a "face," so I would say, "her face lit up," or "grief was written all over his face," etc. With time, through reading, I have discovered that I can say "expression," and "features," and "countenance," and "physiognomy," and many other variations (I don't mean metaphors like "a fist of wrinkles," only synonyms).
I'm reading THE EXORCIST and have just picked up a different way of saying "she looked through the crack in the door," (or gap or whatever), and it's "she looked out through the aperture." Stuff like this can't be found in any thesaurus, it can only be found via reading, and I both love it and hate it. Love it because it's such a wonder to glimpse a new way of saying something old and familiar. Hate it because it takes such a bloody long time to learn all the ways there are to write in rich varied language.