Four weeks after taking office, President Obama has signed the American Reinvestment and Recovery Act - the cornerstone of his effort to stop the U.S economy from collapsing further.

• 就职后四周，奥巴马总统签署了美国复苏与再投资法案-这是他致力于使美国经济停止继续衰退而做出的第一裁澜努力。