There are about 3,000 living languages in the world, but only six of them are the most important (1) ones. Two-thirds of the world's population speaks those languages. More than 400 million people speak English as their (2) mother tongue. Another 400 million speak it as a second language. No one knows (3) how many people speak it as a foreign language. Chinese is the language with more speakers (4) than English, but it is only (5) one language for over one billion Chinese people. English is the official language on one-fifth of the land area (6) of the world in North America, Great Britain, Australia, and New Zealand. In South Africa and India, it is one of the official languages. In many countries, the textbooks in universities are (8) written in English. More than three-fifths of the radio stations (9) broadcast programs in English. More than half of the scientific and research (10) papers are in English. English is the language of international communication.