LOL...when I was in Russia, my translator asked me if I was scared to take the train to Kazan from Moscow (and yes... you should be!) but I told her I was "cool as a cucumber" ... pin ... drop... she had never heard of that colloquialism. She laughed after I explained it and for the rest of the train trip we swapped funny cliches that didn't translate from English to Russian and vice versa. Very entertaining!
