si can be used for reflexive (I wash myself), passive voice (si passivante - eg, "si vende la casa"; literally "the house sells itself", better translated in English in the passive voice as "the house is being sold") or for impersonal constructions (si impersonale - where the subject is indefinite or unspecified; eg, in English, we might say "in Hawaii, people go to the beach", but in Italian one would tend to say "alle Hawaii, si va alla spiaggia"; ie, 'si' has the connotation 'one': "one goes to the beach" - ie, it's the thing to do, but there's no identifiable individual doing it). We could therefore translate "come si cucina il maiale" either as "how does one cook pork" (si impersonale) or, almost equivalently, "how is pork cooked" (si passivante). Without the 'si', "come cucina" would mean "how does s/he cook" - ie, we'd be referring to a specific and identifiable person. See http://www.italian-online.de/grammar/chapter7/7_5_il_si_passivante.htm for a more complete explanation.
The 'Si' is there just as D L translated it. The italians use it reflexively as explained on this page but it can also be a persona pronoun. I cook...You cook.. He cooks..She cooks...ONE cooks..We cook etc.. It is used much more often in Italian than in spoken or written English...I joined an Italian chatroom...they do use it.
No, it couldn't. Your sentence would be: "Come si cucina il suino?"
- il maiale = pork
- il suino = pig
- un porco/a = a sleazy, filthy man/woman
also check this http://forum.wordreference.com/showthread.php?t=362845 (post #2)
One might think that animal names would be stable, as animals don't change as quickly as language does. suino (cf. English swine) and porco go back to Indo-European, but maiale (< Latin maialis) may have originally referred to a castrated pig sacrificed to the goddess Maia. Il maiale can also refer to a living pig. "Le creature di fuori guardavano dal maiale all'uomo e dall'uomo al maiale e ancora dal maiale all'uomo, ma già era loro impossibile distinguere fra i due." (The conclusion of Orwell's Animal Farm in Italian translation.)