Wes, the Wise Expat Sage, has lived in Luxembourg for precisely eight months longer than you and therefore knows everything.

Dear Wise Expat Sage,
 
Occasionally, I’ll be talking with some Luxembourgish parents from my children's school, and we'll be having a decent if not a little simplistic conversation in English, which works for us all except Felix who seems totally ill at ease, but that's probably because he's from the north of the country. 
 
All of the sudden, one of them switches back into Luxembourgish, and they all follow suit. This also happens at work with Luxembourgish colleagues. We're having a perfectly fine conversation about some minor inconvenience I've brought up, such as that my yoga instructor has been ill with a stomach bug for a week, and suddenly one of them hijacks the conversation and plunges it into their maternal language. What’s the reason for this?
 
Rachelle B.
___

Dear Rachelle, 
 
Now that I've lived here for many years and have experienced countless social interactions with Luxembourgers, I better understand their customs, habits, and inclinations. It also helps that I've successfully completed two Luxembourgish language courses, the second one online with a man named Chih-ming whom I later understood was an AI bot and probably mistook Luxembourgish for Flemish, but that's besides the point. 
 
Nine times out of ten, the reason Luxembourgers bring the conversation back to Luxembourgish is because they want to discuss something about which they're very passionate, yet they hesitate to do so in front of foreigners due to the fear of appearing simpleminded or foolish: potatoes. 
 
That's right. No matter if they’re a lawyer from Luxembourg City, a garage owner from Dudelange, or a nurse from Vianden, Luxembourgers love talking about potatoes: their weight, skin quality, smell, and even their temperament. Yes. From what I've gathered while eavesdropping on people in cafes and shops all over the country, Luxembourgers ascribe anthropomorphic traits to potatoes, describing some as kind and generous while others are whiny and unbearable.
 
Luxembourgers are so fond of this topic that they spend upwards of two hours every day talking about potatoes, just as people in other countries obsessively talk about football, the latest ghost haunting, or fluctuations in the price of cotton socks. 
 
Don't take my word for it. I've consulted an acquaintance named Yves, a bona fide Luxembourger who, I can assure you, does exist and is not a personage I’ve created for this advice column. This is what he said:
 
"It's true that some of us are ashamed of our interest in potatoes, but we don't want to be judged by outsiders. You might wonder why we can't simply involve outsiders in our discussions. Well, that is an impossibility because you have to grow up talking about potatoes to understand the nuances of what makes one potato jolly and another moody."
 
Good luck!

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