What is difference between "nel" and "nello" ?
I can't understand what is diferrence between "nel" and "nello"...
What case should I use each words, "nel" and "nello" ?
Both "nel" and "nello" are what we call "preposizione articolata". A mix of preposition and article.
We use "Nel" when we would use "il" and "nello" when we would use "lo" (before "Z", groups of consonants starting with S, and some other group of consonants and before some very rare group of vowels that don't take "l'").
Lo zaino -> Nello zaino
Il cestino -> Nel cestino
L'elenco -> Nell'elenco
Some examples of words with "lo"...
Lo zaino, lo zoccolo, lo scatto, lo stereo, lo scivolo, lo spiedino, lo gnocco, lo pneumatico, lo iato.
You are very welcome. Remember one thing: if ever you come to Italy and try to speak Italian, the Italians will love you for it, for the fact you took all that trouble. Of course you will know more than just hello, goodbye and how much is that, but even if that is the case they are pleased.