[Italian] Stress on Italian words

[Sancho Panther]

When you see a multi-syllabic word in Italian how are you supposed to know where to place the stress without a written accent?

[aleCcowaN]

Dictionaries use stress marks to show that

straordinario
[stra-or-di-nà-rio]
ant. estraordinario
(pl. m. -ri; f. -ria, pl. -rie)
A agg.

1 Che è fuori della norma, dell'ordinario: un fenomeno s.; un fatto s.

[AngelicaDeAlquezar]

@Sancho: There doesn't seem to be a rule, and as far as I know, some words are pronounced differently from region to region.
Although I found some "guidelines" that you might find useful, I'm afraid it's only a matter of getting used to how native speakers pronounce them.

[pinosilano]

El idioma italiano se pronuncia exactamente igual en toda la península e islas.
Puede tener un acento del sur, del norte, del centro, de las diferentes islas, pero la palabra 'straordinario', de AlecCowaN, se entiende en toda Italia.
El italiano es la lengua franca de los italianos, quienes usan más a menudo el dialecto de origen que no el italiano, aunque ultimanente ha disminuido un poco.