Yeah, I think as a general rule, using the plural whenever you can so you skip the article is going to help you test out of skills better. Although I guess the whole point of us deciding to use this course in the beta is to help pick up those little mistakes, so we should be actively looking for them. :/
I'm not sure what you are getting at. What Lili wrote clearly would not help one "test out" better, since it was not accepted. The contributors don't have English usage down perfectly, which is, indeed, why we should do the beta and report any change needed. I don't, however, see a consistent use of the plural or the singular as something they are doing.
Yeah, I understand that in this particular case, the plural wouldn't work. Simply saying they accept the plural as an alternative translation more consistently than they accept different variations on article use. Using the plural would by no means return the kind of results you'd hope for either, though. :/
i've finally returned to this question in the exercises. it is great to see that so many of the suggestions made in these discussion have been implemented.
however, when i tested out the plural option again, i am still marked wrong. i am more than happy to be incorrect, because that way i learn something i obviously didn't understand. but i'm not sure i get why 'food sellers sell food' is not accepted...