The default role of an interpreter is a conduit. Merriam Webster defines conduit as a natural or artificial channel through which something is conveyed. If we think of the channel as a telephone wire, the conduit transmits anything and everything that is received from one end to another. In other words, an interpreter relays all information that is spoken, without any omission, additions, or distortions of the message.
In medical and legal interpreting, there are times when we have to give bad news. And in times like this, the client may become upset and use curse words to express his feelings. In my medical interpreting training, someone raised a question of whether interpreters still need to relay everything in such cases, particularly if an interpreter has qualms about cursing. Despite what an interpreter’s personal feelings are toward swearing, interpreters must stay true to the original message, even if it means cursing or using words they wouldn’t necessarily use in their daily lives. Such is what’s implied in the code of ethics for interpreters.
Regardless of the cultural or social implications of cursing, if it happens that you must curse on the job, then you need to do it as part of your professionalism. I don’t curse, and haven’t really thought about how English curse words correspond with Chinese curse words, but as a responsible interpreter, I’ve put together a short list (you know, for my work, of course). Cursing is an interesting thing. You’ll notice below that the common curse words we use in English relate to sex and excretion and mothers. Even though sex and excretion are unavoidable parts of natural human conditions, and we all love our mothers, these words are considered indecent and taboo in both the American and Chinese cultures.
- Bastard-王八蛋 (wáng bā dàn)、 龜孫子(guī sūn zi)
- Fuck [angry fuck]- 幹 (gàn)、肏 (cào)
- Fuck, Fuck me, Fuckin’ awesome, Holy shit [excitement]-我靠 (wǒ kào)
- Fuck you, Go to hell- 去你的 (qù nǐ de)、 我鳥你 (wǒ niǎo nǐ)
- Fuck him, Screw him-鳥他的 (niǎo tā de)、去他的 (qù tā de)
- Bullshit–屁 (pì)、屁話 (pì huà)、鳥話 (niǎo huà)、你個狗屁 (nǐ ge gǒu pì)
Example: What the fuck are you talking about-你在講什麼鳥話 (nǐ zài jiǎng shén me niǎo huà) - What the fuck is this?-這是什麼鬼? (zhè shì shén me guǐ)
- What the fuck are you doing?-你搞什麼鬼? (nǐ gǎo shén me guǐ))
- Damnit- 他媽的 (tāmāde)
- Son of a bitch- 狗崽子 (gǒu zǎi zǐ)
These are just some common English curse words and their cursory Chinese equivalents. If you’re interested in learning about Chinese curse words, their detailed explanations, and how they relate to English, the Transparent Language blog has a good post about it that you should check out.
Happy cursing! (Just kidding. Cursing is bad.)
Their Words. Your Voice. 
This is very hard to handle when interpreting. I don’t speak much Chinese but in Japanese a lot of curse words just don’t exist. There are times when Japanese use expressions that I think probably merit a curse word to convey how mad they are in English, but they didn’t use one in Japanese so I don’t add one. But vice versa, sometimes someone uses a curse word in English that doesn’t exist in Japanese. My boss used the word “half-assed” in a meeting the other day and all I could say was “incomplete and bad”. lol.
Thanks so much for your comment! It’s very true that there aren’t always direct translations that exist, which is why we always try our best to find the best alternative that fits that target language’s cultural context. While it can be a challenge to figure out how some words translate into a different language, it’s also one of the fun things about translation and interpreting.