Il reste au lit...He stays in bed. You will get to know by the context
maybe this can help you: http://french.about.com/od/expressions/a/impersonal.htm
It's true, it only discusses impersonal expressions using "il est" or "c'est". This link mentions a few more: http://www.laits.utexas.edu/tex/gr/vim1.html "Il reste"="there remain(s)" and "il existe"="there exist(s)" are a couple more, which are much like "il y a"="there is/are". There may well be others.
I couldn't find much else in the way of instruction on this point. I guess you just have to get used to the idea that "il" can be impersonal. I know it's tough at first, but when you get a little more familiar with vocabulary and sentence structure, I think you'll find that it becomes apparent.
Our current sentence, "Il reste des frites", for example: if you translate "il" as "he", then you get "He remains some fries", which is silly. So, knowing that "il" could be used impersonally, you recast it with that in mind.
EDIT: This might prove helpful : http://quizlet.com/44504150/french-impersonal-verbs-flash-cards/
Sygmoral may have been thinking of "Il fait chaud", which is indeed another impersonal construction.
"Il est chaud" would be referring to a thing (rather than the weather) which is hot - for example: "il faut battre le fer pendant qu'il est chaud" = "we must strike while the iron is hot".
Like they said, thanks for your clarification! Since I started practicing with Duolingo, I've been making a list of odd phrases (like this one) that I have trouble with and taking them with me to Sunday brunch with my mom and grandmother, both native French speakers. It really helps to have inside explanations and validations for a few of these. Thank you!
There are French speakers taking this course who are using it to enhance their English abilities. Their presence is a valuable asset for those of us taking if to learn French.
You can regard Sitesurf as a trusted source. When Duo decided to institute the option of donating lingots to fellow students they ought to have had Sitesurf in mind.
Or one of the most meaningless! This phrase is nonsense imo. I'd never say "There remain fries" and doubt the French would say the equivalent phrase in this way either. I'd much more likely say "There are some fries left/remaining". Consequently I'd go for "Il y a quelques frites restantes" or something of that nature.
By deducting that the personal interpretation do not work. And by reading through these discussions, ask as you did here, look it up in some other resource than Duolingo, redo the exercise...
But I do agree some context would be helpful in most cases. There is a reason many classroom courses teaching languages use textbooks with stories presenting the material instead of separate phrases.
"There are some fries left" is strange as translation because "il reste" is active "are left" is passive. The change active-passive is hard to understand but can be acceptable, anyway we CANNOT forget that there is a meaning as active for tihis sentence "he leaves fries" is perfectly acceptable as active version of this sentence. "he leaves fries" (as active) and "there are fries left" as passive. Anyway the passive sentence is more complicated to justify and the translation as passive is considered more free.
No, this is not right.
"He leaves fries" = il laisse des frites - someone masculine has appeared here, that was not in the original sentence.
"il reste des frites" is impersonal active. "il" is not "he" but "it" - literally: "it remains fries".
No one knows who left the fries; you cannot assume that it is "he".
I had a hard time with the audio version of this sentence. It sounded like "prest" which is not a word at all rather than "reste". I was then further confused because the sentence doesn't make sense without context. In English you would never say "There are fries left" without some sort of qualifier at the end like "on his plate" or the various other suggestions people have left here. This is possibly the biggest handicap I've noticed with duolingo, there are some sentences, that when translated, just need more context for them to make any sense.
I love this thread. I thought it was "He stayed some fries." And right before I clicked "Discuss Sentence" I saw it had 98 comments (LOL!!!) - my first clue that I was not the only one staring at my monitor with eyes bugged out, mouth hanging open. This discussion has completely cleared it up for me. Merci beaucoup!!