A. continually B. wasted C. at the top D. means E. causes F. everything G. put H. collecting I. vary J. appeal K. congregating L. efforts M. condemns N. achievement O. occasionally Around two billion people have no access to modern energy, and a billion have it only 1. The smoky stoves that many of them use, the World Health Organisation reckons, produce pollution that 2 around 2 million premature deaths a year. Makeshift cookers also catch fire easily. And lives are not the only things 3. Women and girls in rural villages lose time and energy walking around 4 dirty solid fuels, ranging from crop waste to cow dung. The 5 of a stove that produces more heat, more cleanly and with less fuel is clear. But Kirk Smith, a stove specialist at the University of California at Berkeley, points out that most 6 to promote cleaner stoves have failed. Too much emphasis has gone on technology and talking to people 7, too little to consulting the women who actually do the cooking. When subsidies run out, the schemes have faltered, with stoves left unused or broken. Why might it be different this time? Wouter Deelder of Dalberg, a development consultancy, says that stoves have improved in 8 from the materials used to the design of chimneys. Even so, the new stoves can cost $30 or more. Greater efficiency 9 they pay for themselves in a few months, but the price is still prohibitive for people living on a few dollars a week. Moreover, technology that works well in the laboratory may fail in the field, where fuels, cooking practices and even the shapes of vessels 10 widely.