"This is a tragic thing," "We came into this crisis without the authority and the tools necessary to contain the damage to the American economy posedby the very severe pressures working through the financial system."

VOA: standard.2009.03.24

It's not necessary very well formatted but it looks pretty complex, right?

排版不是很整齐,看起来也非常复杂，不是吗？

哈佛公开课 - 计算机科学课程节选

One of the forms of processing that happens, that's very important in human gene expression is that some of the sections of the DNA molecule are not really necessary for describing the protein.

在人类的基因表达中,有一种非常重要的加工形式,那就是在DNA分子中有一些片段,对于编码蛋白质而言毫无用处

耶鲁公开课 - 生物医学工程探索课程节选

"It is a very essential conversation, that Israel needs to conduct, among ourselves, of what is justified, what is necessary, what is legal and moral, and what even is effective in order to keep our citizens safe."

VOA: standard.2009.09.09

"When the request came through for us to consider re-forming to play, we felt that the immense scale of what had happened in Victoria and the really necessary kind of giving from other quarters to help people meant that it was something we should take very,very seriously,".

VOA: standard.2009.03.14