Question about a phrase I came across in the pre-lesson dialogues:
“… quando si viaggia sia per piacere che per affari.”
“… when one travels both for pleasure and for business.”
I don't remember coming across these combinations in the grammar lessons. I'm used to seeing “sia” as the subjunctive “is” and reading “che” as “that”. Are there other examples of words that change their meanings when combined with “per”, or is that even what's happening here? Any additional guidance?