Back in the 60s, they built a computer to translate between Russian and English. They had a big party to celebrate the first time they booted up the computer, but they had a problem of testing it since nobody was around who spoke Russian. One of the Computer Scientists proposed that they simply feed in an English phrase, translate to Russian, then translate back to English.
They fed in the English phrase: THE SPIRIT IS STRONG BUT THE FLESH IS WEAK
The computer whirred and clicked and spat out the translation.
They keyed the Russian translation back into the computer, which whirred and clicked.
The computer finished its translation: THE VODKA IS GOOD BUT THE MEAT IS ROTTEN