Who exactly rolling over the sands?

Question

In Dune (2021), a girl narrates on the screen:

Girl: My planet Arrakis is so beautiful when the sun is low. Rolling over the sands...you can see spice in the air.

Who exactly rolling over the sands?

Answer 1

Native speakers frequently use "you" as an indefinite pronoun. The meaning here is something like this:

Anyone who rolls over the sands can see spice in the air.

The traditional rules call the usage of "you" as an indefinite pronoun "informal." What that really means is that—traditionally—professional editors did not permit the usage in books or articles of nonfiction. And I suppose that many people who consciously chose their words when speaking avoided the usage as well.

In its place, traditional usage requires "one":

Rolling over the sands, one can see spice in the air.

But to most speakers, especially in America, this usage is no longer natural and has not been natural for a very long time. The most conservative usage guide that I know is Garner's Modern English Usage. The author writes this about the use of "one" as an indefinite pronoun:

one. A. The Overdone one. In AmE, one (= any person indefinitely) is extremely formal. To most American speakers, it seems bookish and pedantic. It’s rare to find anyone who goes this far, especially in speech: “So if one does one’s best, one recognizes that sometimes one’s best is not going to bring all of the changes that one would hope for, but it doesn’t mean there hasn’t been progress.” Bob Krueger (interviewed by Diane Jennings, Dallas Morning News, 31 Dec. 1995,at J1). For ordinary purposes, you is a better, more relaxed choice. The passage above, for example, might have read: So if you do your best, you recognize that sometimes your best isn’t going to bring all the changes that you would hope for, but it doesn’t mean there hasn’t been progress.

Finding a comment like this in a conservative usage guide is a good indication that "you" will soon become the standard usage, and "one" will become a historical oddity.