经济学人下载:影讯猎杀本拉登 美国之夜

They are also easy to extract from blood.
淋巴细胞也很容易从血液中提取出来。

Thanks to improved data analysis, they can now extract from noisy electrical background the firing of single neurons.
由改进的数据分析来看，他们现在可以从嘈杂的电波背景中提取单个的神经元放电情况。
2.touch down 降落，着陆

The report does not explain whether the spacecraft would touch down on the martian moon's surface or orbit around it.
这份报告没有说明飞船是着陆火星卫星表面还是绕它环行。

We should touch down very soon now.
不久我们就要着陆了。
3.believe to 相信

I believe to be a top lifter you have to enjoy it first.
我相信，要成为一个顶尖举重运动员，你必须首先热爱这项运动。

We should all stand together to defend what we believe to be right.
我们应该联合起来,维护我们坚信的正义。