This is very useful for aliens learning Hebrew.
"Hello fellow human. My human friends and I are eating a tasty lemon. Delicious, human food."
I don't think this is an "error" worthy of a report, but it only caught one of my typos... I was corrected for typing תאים but Duo didn't notice that I added a letter when I typed אנאחנו. I think this is an issue with Duolingo itself, actually; I've noticed in other languages that if you make two different kinds of errors (e.g. one misspelled word and one misused accent) it will only correct you for one.
Reminds me of the film Haushpizin where the main character wants to buy an exemplary lemon for his holiday meal.