I think that the main issue with this phrase is that this phrase is something that you will say to someone during a conversation and will not stand on its own like for example asking a question or saying a statement like you are beautiful etc. You need more information before in order for this to make sence.
I'll contribute to the frustration because sometimes piling on is the only way things like this get noticed.
The French subjunctive is a difficult enough concept to learn without the ridiculous mental gymnastics we're put through with sentences like this. Making it all the more frustrating is that there are only three lessons for learning a concept that is so important and yet the few lessons we do have are clogged up with exercises that provide essentially nothing.
There are almost literally countless useful examples of the French subjunctive that could be used and taught in this section. It's almost like someone went out of their way to make these sentences indecipherable.
This section needs to be cleaned up desperately.
Just my two cents Though I agree that some of the uncompleted phrases provided by Duolingo can be difficult and perhaps even frustrating at times, imagine the complaints here if we actually were given the infamous missing context we complain about... "Oh these Duolingo sentences are just too long to get perfect" and "darn it I lost my heart just because I forgot one little word in this long example and if it was just a bit shorter I would've gotten it correct" So at times I find the given example odd and a little off, I just remind myself how freaking awesome this app truly is for the price! In fact, its helped me where even the accredited-tuition-paid-college-course hadn't! Honestly and without exaggeration, DL truly has filled the many voids offered by the course I was accepted into and had paid for in full at the college!
I actually don't mind the sentences without context--one of the ways I amuse myself while I'm doing this is to make up contexts for the strange sentences-- ("i am returning your pig" Thanks for letting me have it, but we didn't need the bacon today, so I'm returning it intact....) But I digress--what does bother me is that common meanings in English are often marked wrong. For example--"Pour, "depending on the context, and certainly in this sentence could mean "in order to," but DL would not accept my translation of that particular "pour" even though it made perfect sense in English (and even though I pictured a little doggie door that was constructed especially in order that he enter here...ah, well.....)