Prior to the 20th century, many languages with small numbers of speakers survived for centuries. The increasingly interconnected modern world makes it much more difficult for small language communities to live in relative isolation, a key factor in language maintenance and preservation. It remains to be seen whether the world can maintain its linguistic and cultural diversity in the centuries ahead. Many powerful forces appear to work against it: population growth, which pushes migrant populations into the world's last isolated locations mass tourism global telecommunications and mass media and the spread of gigantic global corporations. All of these forces appear to signify a future in which the language of advertising, popular culture, and consumer products become similar. Already English and a few other major tongues have emerged as global languages of commerce and communication. For many of the world's peoples, learning one of these languages is viewed as the key to education, economic opportunity, and a better way of life. Only about 3000 languages now in use are expected to survive the coming century. Are most of the rest doomed in the century after that? Whether most of these languages survive will probably depend on how strongly cultural groups wish to keep their identity alive through a native language. To do so will require an emphasis on bilingualism (mastery of two languages). Bilingual speakers could use their own language in smaller spheres—at home, among friends, in community settings—and a global language at work, in dealings with government, and in commercial spheres. In this way, many small languages could sustain their cultural and linguistic integrity alongside global languages, rather than yield to the homogenizing (同化的) forces of globalization. Ironically, the trend of technological innovation that has threatened minority languages could also help save them. For example, some experts predict that computer software translation tools will one day permit minority language speakers to browse the Internet using their native tongues. Linguists are currently using computer-aided learning tools to teach a variety of threatened languages. For many endangered languages, the line between revival and death is extremely thin. Language is remarkably resilient (有活力的), however. It is not just a tool for communicating, but also a powerful way of separating different groups, or of demonstrating group identity. Many indigenous (原生的，土著的) communities have shown that it is possible to live in the modern world while reclaiming their unique identities through language. Minority languages can be best preserved in ______.