Increasing human number places intense pressure on ecosystems and natural resources, and this pressure is expected to increase until world population stabilizes at about 10 billion by 2050 to 2070. （However, this stabilization will be achieved only if present efforts to check population growth are pursued vigorously.）
【正确答案】：但是，只有现在继续强有力地控制人口增长，才能达到人口稳定。
【题目解析】：only if翻译成“只有...才...”；check population growth翻译成“控制人口增长”。
