Juan is not a legal U.S. citizen, but he has permission to live and work in the United States through a "Visa", which acts somewhat like a temporary citizenship card. They also give visas for visiting students and artists.
Articles of confederation
A severe water crisis looms over India. ... A shortage of water will not only deprive millions of their means of earning a living but also it will result in severe foodgrain shortages, which would in turn trigger spikes in food prices, and also deepen India's problems of hunger and malnutrition.
Answer:
An external, arched support for the wall of a church or other building. Flying buttresses were used in many Gothic cathedrals (see also cathedral); they enabled builders to put up very tall but comparatively thin stone walls, so that much of the wall space could be filled with stained-glass windows.