The other night I went to a really boring dinner party. The hosts were busy in the kitchen, and the guests had little in common. It didn’t help that after we finished a bottle of wine, there was no more alcohol in sight. As soon as we put our dessert spoons down, everyone leaped to his feet to leave. I felt bad, as the hosts had made a lot of effort with the meal, and it wasn’t even 11. How early can you leave a boring dinner party? And if you don’t stay long, is there a way to soften the blow for your hosts? —Desperate to Get Out of There

Dear Desperate,

Unlike a boring movie, which you can leave early, you have to stay at least until dessert. The exception is if the dinner has lasted far beyond societal norms—say, four hours, and the host has only just popped the cobbler in the oven. (Your rights in this type of ultralong dinner situation are covered in one of my previous columns.)

In a more typical dinner party scenario, you should stay through dessert, and then linger a bit more. James Nestor, a San Francisco writer who has suffered through “hundreds” of dull dinners, suggests “an hour to an hour and a half of chatting on top of dinner.” Otherwise it looks like you just came for the food.

While waiting for your dinner to conclude, you can’t just zone out. As Winda Benedetti, a freelance journalist in Seattle, says, “If you’re a guest, don’t just sit there twiddling your thumbs and thinking, ‘Oh, I’m so bored.’ If you’re bored, it’s partly your own fault.”

So how do you help make things more lively? Asking questions is a classic technique to juice up the conversation. But skip the obvious ones. I was at a dinner recently where one of the guests attempted to banish a long silence by asking all the other guests: “Do you have any brothers and sisters?” A query like this is the death knell of a dinner party. It signals social desperation. One by one, everyone gave his or her rote answer. Then silence descended again.

Instead, “ask something a little more outrageous or unusual,” says Laurel Sarra, a lawyer in Redondo Beach, California. “Instead of, ‘How did you meet the host?’ ask, ‘What do you have inside your survival kit?’”

Or do as Nestor does and try psychological quizzes. “They might be cheesy, but it’s better than sitting there saying nothing but, ‘Mmm, this is good.’” Nestor prefers a variation of this game. If it’s after dinner and you’re willing to commit to staying another hour, suggest a parlor game, like Fictionary or Mafia. Competition gets the adrenaline flowing and perks people up.

If you’ve put in an hour on top of dinner and you just can’t get the conversation off the ground, start clearing the table. Doing the dishes is a tactful signal to your hosts that the evening is over. It’s also a small compensation for the failure of their dinner party.

When you leave, smile and thank your hosts, but don’t fabricate an excuse. Leaving a dinner party is like getting off the phone: There’s no need to apologize or explain it. Just say, “I have to go.” As Sarra says, “There’s a certain elegance and dignity in not having to explain yourself.” Sarra also points out that if you offer an excuse, you set a precedent, and next time you want to leave, you’ll have to explain why. If you’re lucky, of course, there won’t be a next time.

Table Manners appears every Wednesday. Have a Table Manner s question? Email Helena.