0 short for stamped addressed envelope or self-addressed envelope, an envelope on which you write your name and address, and put a stamp on so that someone else can use it to send you something -- busta affrancata per la risposta
Please enclose an SAE.
We can complete it step by step however long the road is and it can't be completed however short the road is if you don't even mark your footprint.
Possiamo completarlo passo dopo passo, indipendentemente dalla lunghezza della strada, e non può essere completato, per quanto breve sia la strada, se non segni nemmeno la tua impronta.