I am still so confused about when to use the definite article. For example, here we use it in Italian but not in the English translation. But when preferring carne or pesche (another example in this lesson), we don't use the definite article in either the Italian or the English. There are many other examples of this confusing situation.
To everyone commenting that "fall" is a vulgar Americanism, it was used interchangeably with "autumn" in England in the 17th century, when English speakers were first settling in America. Like a lot of other terms we think of as Americanisms, it fell out of favor in England -- in this case, sometime in the 19th century -- while remaining in use in America. Duolingo accepts both.
Italian verbs conjugate or change endings for each kind of pronoun:
io preferisco I prefer
tu preferisci you prefer
lui/lei preferisce he/she prefers
noi preferiamo we prefer
voi preferite you prefer
essi/esse/loro preferiscono they prefer
You can look a verb up on Wiktionary and then click on Conjugation, currently we are using the Indicative Present tense. https://en.wiktionary.org/wiki/preferire
Sorry, sorry my mistake! The word autunno clearly does not translate a Autumn, but "Fall". It must be all the speaking English where I am going wrong.