Situation: You find yourself walking alongside a casual acquaintance and you don’t want to chat all the way to your destination.
Solution: If you can do it discreetly and naturally, turn a corner or “duck into a coffee shop or public restroom,” says Leil Lowndes, author of How to Talk to Anyone (McGraw-Hill, $15, www.amazon.com). But if that isn’t an option, it’s best simply to bring up a topic you enjoy talking about — something that elicits more interesting comments than last night’s TV shows. Excited about an upcoming vacation? Ask the person about her last trip or for a book recommendation for your flight.

Situation: You see someone you think you recognize but aren’t sure if he recognizes you, so you don’t know whether to say hello.
Solution: “If you pass someone on the street, you can let it go without talking,” says Jodi R. Smith, president of Mannersmith, an etiquette consulting firm based in Boston. “But if you’re sitting in a doctor’s office or at a party, say something.” Start with your name, followed by one piece of information about yourself. Saying, “I’m Clare. I went to Vanderbilt, and you look very familiar. Have we met?” is a better option than interrogating the person. If you’re fairly certain that you met the person in a specific place and just aren’t sure that he remembers you, “that can be a natural opening for a conversation,” says Caroline Tiger, author of How to Behave: A Guide to Modern Manners for the Socially Challenged (Quirk, $13, www.amazon.com).