"We lenen soms de stofzuiger van mijn ouders."
Translation:We sometimes borrow my parents' vacuum cleaner.
Hmmm. Translation given at the top of this discussion correctly shows "parents'" with a possessive apostrophe. Yet in the exercise itself, inclusion of the apostrophe is marked as a typo, and the correct translation given as: "parents" (no apostrophe). Doesn't seem to be any way to report this, so reporting it here.
Submit a bug report. It's not a thing we can solve: https://support.duolingo.com/hc/en-us/articles/204728264-How-do-I-report-a-bug-
You "borrow" something from someone. You "lend" something to someone. When you get a book from the library, the library is lending it to you, and you are borrowing it from the library. When someone needs some cash (that they'll pay back), you lend it to them, and they borrow it from you.