But if someone asks you, and you say: 'Oh no, I have a wife, ' you're done, it's clear, you can do whatever you want.

CNN: In the Field

This means that if someone asks for leftovers, you say, "I'm so glad that you enjoyed the meal, " and wrap up a wedge of quiche.

CNN: Navigating family and dinner table etiquette landmines

But what are we supposed to do if someone as yet unconvicted asks to use our services?

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"Now when someone asks if our Rieslings are sweet, we say, 'No, they are Ohio Dry, ' " Mr. Loosen said with a laugh.

WSJ: Demystifying German Riesling White Wines | On Wine by Lettie Teague

As the doctor prods the wound with finger, Henrie says the bullet feels like fire in his leg, and he asks if someone has gone to get his mother.

NPR: Dodging Bullets to Vote in Haiti's Cite Soleil

For example, if someone from "IT support" calls you and asks for your password so they can help fix your problem, how do you know they haven't called everyone else in the building first until they found you who has really got a problem?

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