A、Natural disasters can account for disappearance of languages. B、The acceleration of language death didn’t start until 200 year

Half of the 6,000 or so languages spoken in the world are under threat and a wealth of human knowledge could be lost with them, according to a new study. The study says pressures from dominant languages such as English, French, Spanish and Russian are drowning out minority tongues at an accelerating pace. "The dying and disappearance of languages has been going on for thousands of years as a natural event in human society, but at a slow rate," says the study funded by UNESCO. "However, the past 300 years or so have seen a dramatic increase in the death or disappearance of languages leading to a situation today in which 3,000 or so languages that are still spoken are endangered, seriously endangered or dying." The study cites several reasons for the disappearance of languages, ranging from repressive government policies and assimilation to economic pressures, migratory trends, disease and natural disasters. While sounding the alarm, it notes that a determined multilingual approach can rescue even the most threatened tongues. In Japan, only eight elderly people spoke Ainu on Hokkaido Island by the late 1980s after decades of official neglect, but promotional policies have since revived the language.