Latin is consisted of multiple moods, tenses, declensions, conjugations, and genders - all of which are heaped upon countless grammar rules, exceptions, and different ways to translate. The difficulty of learning Latin also includes relentless barrages of vocabulary terms, which form the very foundation of Latin understanding. You can have one word for the noun "bird", but two dozen words for the verb "strike" since each word had a different connotation and - according to the Romans - had to be used in a very specific way. Take into consideration, also, the thousands of idioms and metaphors the Romans loved to use and you have a very difficult language to properly and effectively translate.