As an Englishman living and working in Paris for a few years, my eyes have been opened to the difficulty of working in another language. I used to be a little bit dismissive of foreigners who hadn't completely mastered English but now I realise that they were almost fluent. On the other hand, I haven't really managed to master French at all.

His observation about becoming introverted in a foreign language is something that I experience too. Something that he didn't mention though is that often people will assume that you are stupid if you can't speak their language fluently, this is made even worse since you are indeed dedicating 80% of your brain just to following the conversation, so that in a sense they are correct in their judgement at that moment in time. It's painful to be on the receiving end of this and again this is something that I was unconsciously guilty of when I lived in London.

We just need to occasionally remind ourselves when the other person is not speaking in their native language that they are having to do a lot of extra work just to communicate with us.