入乡随俗 [rùxiāngsuísú] is one of those rare 成语 you come across, translate literally, and almost immediately know what the English equivalent is. So let’s translate it literally, and then I’ll give you an opportunity to guess what the meaning is.
入 [rù] enter
乡 [xiāng] village
随俗 [suísú] follow local customs
So, “when you enter a village, follow the local customs.” Any ideas?
If you said “When in Rome, do as the Romans do” well congratulations, you nailed it! If you know how to use “When in Rome” in English, then you know how to use it in Chinese. Your Chinese friend offers you 猪脑 [zhūnǎo] or ‘pig brain’? 入乡随俗! You’re asked to participate in a traditional festival? 入乡随俗! This isn’t just useful vocabulary: this is the mindset you should have when you make your first journey to China (or anywhere, for that matter)! You won’t regret it!