Living in a culture that is not one's own requires a good amount of mental energy. First one has to discipline one's self to not assume that everyone does things the same way (and not to assume that one's culture does things the "best" or "right" way) and then one must be disciplined to be open to other ways, thoughts, and habits.
As Americans we are well indulged in our way of doing things. We can travel fairly far and still find ourselves in our own culture. From the east coast to the west coast (and into Canada) we encounter the same language, same TV shows, same stores, same restaurants and for the most part similar styles of dress. Each region may have a particular flare/personality but if you don't like it, you just head for the Gap or McDonald's.
In Belgium, we can find bits and pieces of American culture and those touchstones are helpful. We get some American TV, in the Chievres commissary and PX we can find American products, and on base the primary language is English.
Some people can and do limit themselves to speaking English the entire time they live here and socializing only with Americans and only shopping at Chievres.
It is hard work to push beyond one's culture. Mentally I am always converting things. Like road signs - they are all in French (except when they are in Flemish). For many weeks I traveled down a road that displayed a caution sign. I knew I was to be aware of something, but didn't know what. The sign said "ornieres" As a family we had a running debate about these dangerous ornieres. Was it farm equipment? an animal? Eventually, I looked it up - ruts.
Telling time is a process of conversion. Europeans use military time. On Monday's Kyra's dance class begins at 1800, on Wednesdays at 1900, on Fridays at 1700 and on Saturdays 1430. The clocks in our home are set for military time. Whenever it is 15 something, I always have to pause and figure things out. Perhaps in another few months I'll just know or maybe not.
My oven is Celsius - my recipes are Fahrenheit as are all the heating instructions on products bought at the commissary. I have a Celsius/Fahrenheit conversion website on my Bookmarks bar.
To figure out the day's weather is a two step process. First I find a weather website then I go to the conversion website. I do know 6 (today's low) is cold but I don't know how cold (43) and I know that 15 (today's high) will feel better (59) but how warm can I expect to get?
These are simple everyday things - cooking, telling time, driving down the road. We do them without thinking - unless even these things are foreign.
In learning a language there is a stage that sometimes comes after much time and persistence - the stage when one begins to think in the other language without translating out of or into English first. I hope that stage comes for me when I am not constantly converting language, culture, time or numbers. It will probably happen right before we move back to the U.S.