General feedback for Spanish
I have noticed two things.
First sometimes the accepted answers are very literal translations and some are idiomatic. This becomes especially problematic on the real world translations when you end up with a literal translation as the most popular or "correct" translation of a phrase that should not be translated as such.
Secondly, the flag for Spanish is that of Spain, but when the lessons involve idiomatic language, they are latino idioms; and there is no use of the vosotros forms which are common in Spain. It is somewhat misleading.
It's the same with French... there should probably be some sort of thing that alerts you that what you are learning is an idiom.
My own translations tend to be idiomatic, and are - therefore, I think - often marked as in- correct. Just the same, my criterion will be to continue to attempt to answer the question, "what would an expert, fluent real-time translator say?" It seems to me that is the only way to progress, since - given the Duolingo approach - there is no "god of language" making judgements. As to idioms, once again, there is no "god" out there, so it's up to us. If I don't get the idiom, I've found the only way is to do an on-line search. For example, since I like the recipe translations, and know that cooking terms are often in, or come from French, digging around in an on-line or hard copy French dictionary really can help even though I'm trying to translate from Spanish. Dunno if that helps much.
What I take issue with was that I'll do an idiomatic or human translation and have it marked wrong, so I start doing literal translations and then one of those gets marked wrong because the accepted answer is idiomatic. I would just like for some consistency. Accept both or accept only one type. The mix and match is confusing.