In winter, move the plant to a cooler spot***,*** around forty degrees.
My question is why does put a comma before around forty degrees? "around forty degrees" is not an independent sentence. Is it a nonrestrictive phrase
1 Answer
The end of this sentence is just kind of tacked on; it isn't part of a really correct written grammar. Instead, it's an imitation of how people speak. A comma is not really the best punctuation here.
A common, and perhaps the best, way of writing this is with a dash:
In winter, move the plant to a cooler spot—around forty degrees.
Note that this long dash is called an "em dash." Word processing software generally converts three hyphens to an em dash automatically.
You could also use a colon there. That's a more stuffy way of doing it:
In winter, move the plant to a cooler spot: around forty degrees.
