Yes, pinyin is used in such cases. After all, some of these words will even become loanwords in the English language. Who talks about dumplings anymore, when we can talk about ‘Jiaozi’?

However, writing whole sentences in pinyin to try to show off the Chinese that you picked up off some tart in a bar is just cringeworthy. Go to Xinhua bookstore and pick up a good ‘Chinese for beginners’ coursebook and study alone, please. Then use your Chinese on QQ. Even your bar tarts can do that together with you.

You seem a very sensitive and judgmental soul, John; why would you cringe because a body does a harmless bit of showing off, a weakness that we all can be prone to. Anyway, I'm not sure what this slutty bimbo bar talk has got to do with the couple of taglines I have used, like 'wo shi dui de hai shi wo shi dui de?' which another poster said could be replaced by 'dui bu dui' although I can't see how. The point is this though 'wo shi dui de hai shi wo shi dui de' is unlikely to be learned in a bar-it is a statement really that something is the unassailiable truth;whereas dui bu dui doesn't seem to fit the bill...but, I am a learner; you tell me? You can teach me something if you like?