By Eileen McDougall -BBC Feuture Edited by Vinuri Randula Silva Nepal's Kusunda language has no known origin and a number of quirks, like no words for "yes" or "no". It also has only one fluent speaker left, something linguists are racing to change. Through the winter mist of the hills of the Terai, in lowland Nepal, 18-year-old Hima Kusunda emerges from the school's boarding house, snug in a pink hooded sweatshirt. Hima is one of the last remaining Kusunda, a tiny indigenous group now scattered across central western Nepal. Their language, also called Kusunda, is unique: it is believed by linguists to be unrelated to any other language in the world. Scholars still aren't sure how it originated. And it has a variety of unusual elements, including lacking any standard way of negating a sentence, words for "yes" or "no", or any words for direction. According to the latest Nepali census data from 2011, there are 273 Kusunda remainin...