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   If we look a look at how people in Europe communicated just one hundred years ago, we would be very surprised to find out that English was hardly used outside the United Kingdom. The language most commonly used between people of different nationalities was French. However, that is not the case nowadays. English has replaced French as the international language of communication. Today, there are more people who speak English as a second language than people who speak it as a first language.       There are many reasons why English has become the language of international communication. Britain's colonization of many parts of the world had something to do with it, but it is mainly due to America’s rise to the position of major world power. This helped spread popular American culture throughout the world bringing the language with it.       But is it good that English has spread to all parts of the world so quickly? Linguists have suggested “Esperanto”, an artificially put-together language, as a solution to international communication problems but without success. So English will continue being the world language until some other languages, maybe Chinese, which is the most widely- spoken native language in the world, takes over as the world’s international language instead of English. 

What does the world “which” in paragraph 3 refer to?