Breakdown of La carta, la gettano nel bidone rosso.
rosso
red
la carta
card, paper
la
her/it (direct object)
nel
in the (in + il) / while / upon (doing something)
Questions & Answers about La carta, la gettano nel bidone rosso.
Why is there a la before gettano when we already said La carta at the start?
This is a perfect example of left dislocation. Because the direct object (La carta) is moved to the front of the sentence to make it the main topic, Italian requires a matching pronoun to refer back to it right before the verb. Since carta is feminine singular, we use the pronoun la ("it").
Could I just say Gettano la carta nel bidone rosso without moving it to the front?
Yes, that is the standard word order and it is completely correct. However, pulling La carta to the front (and adding the comma and la) shifts the focus. It makes the paper the main topic of conversation, much like saying "As for the paper, they throw it in the red bin" in English.
Why is it nel bidone instead of in il bidone?
In Italian, when the preposition in is followed by a definite article like il, they must combine into a single word. The combination of in + il becomes nel. You cannot leave them separate. We use the article here because we are talking about a specific, known container (the red bin).
I usually hear buttare for "to throw away." Can I use it instead of gettare here?