How often do you guys speak English? All the Norwegians I've met speak basically flawless English.

I'm an American living in Thailand now. I've met a lot of people from all over the world here. Usually when I meet a group of people from France, Japan, Korea, etc they often don't have the best grammar and have to switch back to their native language to discuss what they are really trying to say in English. Or they say things in their native language accidentally out of habit. Even Germans and Dutch, while very good speakers, tend to make small mistakes here and there.

However, Norwegians, and other people from Scandanavia never seem to do that. If I didn't know better I would think that English was the national language and they all grew up only using English, like we do in the US/UK/AUS wherever.

So how often do you guys speak English in daily life? And how did you learn to speak so well?