I put "It misses September," and got the correction "It's missing September." It seems like something is wrong here, but I'm not sure what.
I've never heard "it misses" to mean "it is missing", in the sense of lacking something. "It misses September" sounds to me like "It is noticing that September is no longer here"
Does this help? I'm not sure what else might be causing you problems with this sentence, but I'll help if can.
That's true, I've gotten into the habit of being exactingly literal on Duolingo to stave off any accidental mistakes caused by trying to make a sentence "sound" better to me, so I guess that killed me this time.
Where could a month have gone??? I put It misses september expecting some logical sentence.... =\
September's lacking. This idiom makes more sense than the rhetorical situation with a calendar and some white-out.
Imagine you're going through a stack of files, looking for the invoice from a purchase you made last year. It's not in June, or July, or August--wait, September is missing?