"My house is on a very pretty and small island."
Translation:بَيْتي في جَزيرة جَميلة وَصَغيرة جِدّاً.
Actually this sentence is confusing a bit even for an Arab like me. What they SHOULD have typed is جدا after every adjective. Writing Jiddan after one adjective to be collective for the two adjectives before it can be quite confusing. The English sentence also has a mistake I believe. It should be: My house is on a very pretty, small island or on a very pretty, very small island
So, I guess it is not your fault, but Duolingo's
The translation hasn’t been changed despite the comments and the ambiguity remains after a year of comments!