This thread brings back (not too fond) memories of perhaps my very first international 'gaffe'.
I was about 14yo and I was on a long weekend in Paris with my parents - I had been
'doing' French at school for two years so I was, of course,
totally fluent (yeah - right

(I was a typical 'know-it-all' 14yo...). My parents spoke no French at all, so it was down to me.
The scene: A pavement cafè near 'Les Halles' (the huge Paris covered market).
The problem: How to 'strain' the tea leaves when pouring from the pot to the cup?
The solution: Ask the waiter for a 'tea strainer' - fine so far - yes? So after a very fast, (crafty

) look at my pocket doctionary, I awaited the 'garcon'.
The outcome: I asked him - pointing to the tea-pot - for a
pissoir and just couldn't understand his look of utter horror

.... What had I said? I tried to explain to him with copious hand signals and movements that all we wanted was a tea strainer....Then it suddenly dawned on him what had happened

...he took me by the hand - all the while laughing his head off

- and 'dragged me' around the corner where he pointed to a street urinal and said
"Pissoir" . Then back to the cafè - back behind the bar where he pulled out a tea strainer and pointing to it said
"Passoir"!!! I have not - I promise you -

drunk tea in France
once since that day!