United States Agriculture Secretary Tom Vilsack said no one single nation can fight agricultural greenhouse gas emissions and increase food production at the same time.

VOA: special.2010.01.05

Right now the total value of single-family homes in the United States is about twenty trillion dollars and the market has been becoming increasingly speculative.

如今,美国家庭的,房产总值,接近2万亿美金,而且,市场变得越来越投机

耶鲁公开课 - 金融市场课程节选

This was a very--a single experiment done within the United States, but the idea is appealing, that people are connected to one another via chains of people.

这个实验是在美国做的，但它揭示了一个很有趣的规律，人都是通过一连串的人和另一个人有着某种关联。

耶鲁公开课 - 心理学导论课程节选

Since 2008 the United States has not sold a single grain of rice to Cuba.

VOA: standard.2010.07.29

Many of the abstentions and 'no' votes were cast by member states that said they are opposed to resolutions that single out specific countries for censure.

VOA: standard.2009.11.20