Language problems
By far my biggest language problem is communicating with the Japanese, but sometimes other English speakers also present difficulties. This weekend I had volunteered to help show the Australian rotary club around my town. I was also supposed to act as a translator, which was a disaster because my Japanese is no where up to translating standards. (I have a hard enough time just getting by myself, without translating for somebody else.) And with the thick down under accents, I had a hard time understanding the Australians sometimes as well.
After lunch, someone was handing out ice cream, and I refused saying, "No thank you, I'm stuffed."
There was a pause in the conversation, then one of the Australians asked, "what did you just say?" I repeated myself, and they broke out laughing. "If you come to Australia, don't ever say that," one of the women told me.

And then I remembered a previous conversation I had with a British friend, who was talking about his sexual frustrations with his girlfriend. "She probably wants to be stuffed by me just as much as I want to stuff her, but the opportunity has not presented itself." I had understood the imagery well enough at the time, but I guess it had not occurred to me this was a phrase I would want to be cautious about.
So needless to say I felt a bit embarrassed when I realized what I had said. It was one point for the Australians.
But I was able to laugh at them later, when they were talking about "the negro on TV last night." And I told them if they ever went to America, it was best to avoid using that word.