Just realised this is Mexican Spanish eg potato in Spain is patata. Duolingo shows it as papa.
If you look at the description provided for the Spanish course, this would have been clear.
Spoken in 21 countries, many with beautiful beaches and ancient cultures, Spanish is one of the most important languages in the western hemisphere and the third most spoken language in the world. On Duolingo, you'll learn a version of Spanish closer to what you'd hear in Latin America than in Spain, but the differences are relatively small and everybody will be able to understand you.