Seconded National Experts (abbr. SNE) are like the Erasmus students of the institutions: they already work in the administration of a Member State (abbr. MS) is how eurocrats call a country which is part of the European Union. Clear writing guidelines recommend using EU country or EU countries instead, but some habits are hard to die.... and are lent to the European Union for a short period of time (from a few months to a couple of years). So they have to move to Brussels (abbr. BRU, French: Bruxelles; Dutch: Brussel), officially the Brussels-Capital Region (French: Région de Bruxelles-Capitale; Dutch: Brussels Hoofdstedelijk Gewest), is a region of Belgium comprising 19 municipalities, including the City of Brussels, which is the capital of Belgium. The Brussels-Capital Region is located in the central portion of the country..., usually with their families (a certain level of seniority is required to become SNE), and survive the shock of the first months.
Maybe languages are not their strength but they have a lot of experience in other fields. In general, they are quite relaxed as they know they are just passing by and taking a break from their routine.