I was in a new country hardly any knowledge of the language and I was in a pub with one friend and his friend. My friend went to the bar to get more drinks, he was a long while queuing, and his friend said something to me I didn't understand but then I heard the word toilet (he wanted to use the gents and not knowing what I was saying I said " Ah go f....off, thinking that meant yes go ahead, I said it very loud because of the noise but all the people stared at me. Later my friend explained what I had told his friend and I was totally ashamed and couldn't believe what I had said, I must of heard this "expression" somewhere. really embarrassing