I had no idea that one simple comment would set off such a huge argument.
When a woman had made such a mistake, there was only one way to repair it,—to accept it. One folly was enough, especially it was to last for ever; a second one would not much set it off.
He set off in search of better opportunities.
Don't set him off or he won't shut up all day.
What a tragedy, that someone would set off a bomb in a crowded place.