In steamy Shanghai a few years back I inadvertently developed a way to thwart the sales pitches of overbearing street hawkers.
Guessing the country I was from, said peddlers would try every approach: "Hello!" "Bonjour!" "G'day!" "Hallo!" "Hola!"
I responded with "kia ora".
This silenced them. They'd immediately cease haranguing to whisper among themselves; the question of which arcane language had been uttered was apparently more pressing than the sale of another Mao Zedong figurine.
The Maori greeting of course is now a welcome part of our country's furniture.