填空题

Fifty years from now the world’s population will be declining, with no end in (36) .Several centuries from now, unless people’s values changes (37) , there could be fewer people living in the entire world than live in the United States today. The big (38) of the past twenty years is that in not one country did fertility stop falling when it reached the (39) rate -- 2.1 children per women. In Italy, for example, the rate has (40) to 1.2. In Western Europe as a whole and in Japan it is down to 1.5. The evidence now (41) that within fifty years or so world population will (42) at about eight billion before starting a (43) rapid decline. That has really posed a great deal of anxiety. (44) , many people still fear that it will keep "exploding" until there are too many people for the earth to support. But (45) . World population was growing by two percent a year in the 1960s; the rate is now down to one percent a year, and (46) .This view is coming to be widely accepted among population experts, even as the public continues to focus on the threat of uncontrolled population growth.