Oh, brilliant... That's DUOLINGO DOGMA in a nutshell.
Yeah, why bother using "actual" sentences people would actually say... What a silly idea, right? Maybe we should just have every sentence on here in every language lesson be a fictitious statement, to help us "learn" how to speak that language... Really? Wow, sounds even more dumb as I type it.
The Latin lessons pretty much do that. This Dogmatic thinking is why DL has a pathetic Latin course with hundreds of useless sentences about drunk parrots speaking with dolls and burning cities. Truly embarrassing.
Have you ever read a book? Most will have sentences you have never encountered unless you have read the book before. Just because you can't fathom this sentence, doesn't mean it doesn't exist or is fictitious (I suspect many people wouldn't say that 'a husband is a mother').
The reason the Latin course is the way it is, is because they haven't updated it yet, not because a commenter like me defended a silly sentence that isn't that deep.
If you don't like the content, move on and find some other course. Otherwise, calm down, most people say useless sentences everyday.
The Latin course is no different in that regard as any other course I've taken. The same goes for the ones I haven't taken from what I've heard.
They all have non common and in some cases nonsensical sentences to test your ability to translate as opposed to guessing an assuming. Ofcourse the majority of the sentences need to be normal to give you a good foundation.
You are here to learn a language, not common acceptable things to say. This isn't a course for aliens learning about human culture and wishing to blend in. Indeed they shouldn't be given unusual sentences.
Look at the next sentence.
The boy carries the elephant. (In latin*) You shouldn't go like ow well that can't be it so I'll switch it around, a boy isn't strong enough to carry an elephant. No, this isn't a course about common sense or physics.
You should go like ow elephant is in the accusative form so he must be the one that is being carried. In that case you are learning the language.
*so Puer elephantum portat or even Elephantum puer portat. This 2nd sentence makes this whole point clear. Order and logic would make you think the elephant is carrying the boy, but if you translate it correctly and look at the cases they are in you see that that isn't what it means.
Btw it is not wise to end your comment with "embarrassing", as remarks like that can backfire..
I do feel however that some sentences are more suitable for this than others. There shouldn't be interference from other things, one confusion at a time.