Josep hit the nail on the head, but you don't think about your own language when you speak your mother's tongue. I don't, do you? Somebody else's tongue gets interesting.
"Of course" tells the story of how English came through the gauntlet to become the international these days. In a generation another language could depose the king, long live English. I have taught English to Swiss bankers, CEO's, commercial airline pilots, military people, VIP's, film stars, sports stars, medical people, computer people, it's all being done in English these days.
In South America a secretary who speaks English has a bigger salary than a lawyer, money usually makes things more important, in my opinion.