[David]

If she's with a guide the language shouldn't be much of a problem but I was surprised by how many people didn't speak English. A notepad and pin to write down where they're going to show a cab driver helps. Or do like my girlfriend did and write down every restaurant we might visit with their address and hours to show the cab driver.

It's really strange for us Americans but large tipping is not needed or expected. An extra Euro or maybe two at most is more than enough.