"Corinna learns Latin."
Translation:Corinna linguam Latinam discit.
Because Latin is a declension language. Therefore, the endings of nouns and adjectives differ from one case to an other. You pick a case according to the grammatical function of the noun/adjective.
In a (very) broad outline, here are the cases according to the grammatical functions (to take with a grain of salt due to the many subtleties):
- nominative => subject, noun complement
- vocative => direct address to someone (something)
- accusative => direct object
- genitive => possessive phrase
- dative => indirect object
- ablative => a lot of things...
In the sentence at hand, "Latin" is object so it must adopt the accusative case. In that case "ligua latina" changes to "liguam latinam".
If you keep "Corinna lingua latina discit", "lingua latina" can be:
- nominative and then the sentence would mean "Corinna, Latin learns" (as in Latin itself is learning something) or "Corinna Latin learns" (as in a character called "Corinna Latin" is learning something.
- vocative and then the sentence would mean "Latin, Corinna learns" as if you where shooting to a person called "Latin"
- ablative and then the sentence could mean different things, like for example "Corinna learns thanks to Latin"...
All of which does not make much sense and does not fit with the english translation.
Apparently, studere (studeo) means "to dedicate oneself to" more than it means "to study" and so needs an indirect object rather than a direct object, and Latin is touchy about having the correct case ending.... Until I saw that (thank you Rae!), it didn't make sense to me.
- studet = studies
- discit = learns
We could admittedly argue that the two words mean almost the same in that context but there is still a slight difference between the two.
Maybe Corinna has a gift of instant language learning and, as such, learns Latin without studying it. Or maybe she is very bad at learning languages and therefore studies Latin without achieving learning.