title_body: Are Esperanto's part of speech endings actually beneficial? I was wondering if they really serve any practical advantage.
  
  For one, what they mean depends on what the innate part of speech of the root is, which isn't marked except through the part of speech endings. For instance, attaching the verbal suffix -i to an adjective gives a different meaning than attaching it to a noun. 
  
  Further more, Lingua Franca Nova has a rather novel method of marking mart of speech: its own derivational morphology. Unlike Esperanto's affixes, LFN's affixes often transform a specific part of speech into another (or sometimes just leaves it the same). In this say, suffixes that derive nouns are automatically mark the noun for part of speech without the need of an additional affix that serves no other purpose.
  
  But of course, I'm not exactly fluent in the language myself, so I'd like an opinion from people who do actually know and use this language. Are the part of speech endings really useful or are they just a convoluted way to derive new words?
upvoted_answer: For those unfamiliar with Esperanto POS suffixes, 
  
  -o noun  
  -i verb (infinitive)  
  -a adjective 
  -e adverb 
  
  
  For example:  
  
  sano - health 
  sani - to be healthy
  sana - healthy
  sane - healthily
  
  
  Since Esperanto has free word order, having POS markers allows the differentiation between the following phrases:
  
  ĝoje knabino ludas - a girl plays happily
  ĝoja knabino ludas - a happy girl plays
  
  
  Esperanto and LFN have a very similar affix system, however unlike LFN, Esperanto root words have no innate part of speech, so there is no way of "adding" a verbal suffix to a noun or an adjective. Rather, you would be changing the nominal/adjectival suffix to the verbal one and forming the verb based on the root word. Knowing the POS of any given word makes understanding unfamiliar words a lot easier, which is very advantageous for an auxiliary language. 
  
  With that being said, in EO poetry, nouns often drop their -o ending for aesthetic reasons.
  
  
    Berlino sen vi estas urb' (urbo) sen harmoni' (harmonio)
    Estas trista, trista, amasloĝej' (amasloĝejo)
  
  
  Between EO and LFN's, there is no "better" affix system. They are just two different ways of doing the same thing.