There are 2 billion people in developing countries without adequate sources of light.
ihe dị ka ijeri mmadụ abụọ nọ n'ógbè ndị dịpụrụ adịpụ nke mba ndị ka na-emepe emepe enweghị ọkụ eletriki, mba ndị na-emepụta ihe onwunwe ejighị ihe kpọrọ ihe