As they say, there are two rules in improv: Never say no, and never ask why. When another actor asks 'Why?' or says no to something you're suggesting, then it's very clear that they're putting the onus on you, because they're not comfortable with it themselves.
“You know, the period of World War I and the Roaring Twenties were really just about the same as today. You worked, and you made a living if you could, and you tired to make the best of things. For an actor or a dancer, it was no different then than today. It was a struggle.”
“You have different sorts of people in life, so why should it be any different in football?”