I taught one of my account reps at Toppan how to swear in English on Saturday. Isaka-san speaks really good English and was my daily contact in setting up this job before I came to Tokyo. Really nice guy and probably the only one here who gets it (sort of) when I am making a sarcastic joke. He asked me "What is a four-letter word? That phrase is in the book I am reading in English (John Grisham's Pelican Brief) and I don't know what it means." I start laughing nervously, and then make a list of synonyms that he cross-references in his handheld Japanese/English dictionary: cuss words, swear words, dirty words, curses, obscene words, an oath, 'bad words'. He's still not totally getting it, saying "You swear an oath before a judge, right? So how does this fit in?". So I list four-letter words: shit, hell, damn, fuck. I then explain that all four-letter words are NOT four letters (very confusing) -- he writes down "bastard". Exactly! Not four-letters. (But then he wants to know: what is a bastard, and why can't you call someone that?) I decide to leave cocksucker and motherfucker off the list coz he's only going to get himself in trouble with those ones. I give some examples of how these words are used in sentences "Shit, the color on this proof looks awful!" Or "I am really upset that I missed my goddamn train!". Then I make him promise not to use any of these words when talking to clients.
He thinks I'm a good enough teacher to teach English in Tokyo.