By 2050, there’ll be about 32 million people in the United States over the age of 80, and unless we do something about it, half of them will have Alzheimer’s disease and three million more will have Parkinson’s disease.
到2050年时，美国会有3千2百万人 年龄大于80岁，如果我们还不采取措施的话 他们中的一半会得老年痴呆症 三百万人会得帕金斯症。