In other new research, a study has found that circumcision does not decrease the risk that H.I.V.positive men will infect women.

VOA: special.2009.07.29

I'm going to say, quite to the contrary, the positive charge is concentrated at the center in a tiny, tiny, tiny volume.

我要说的是，完全相反，正电荷集中在中心,在一个非常非常小的体积内。

麻省理工公开课 - 固态化学导论课程节选

I think it's also the struggle of a generation trying to enrich the public square with positive conversation about religion.

我认为这也是我们这一代人的努力,我们试图通过积极地谈论宗教,来丰富社会生活。

普林斯顿公开课 - 人性课程节选

My work required deep concentration and I am positive that I would have been a far more efficient worker had I had a small office with a door that I could close when I needed to concentrate.

BBC: The pleasures and perils of the open-plan office

Now my views have definitely changed as I am positive that what I saw that morning was something very unusual.

BBC: Surrey puma sightings: Timeline

I'm positive and I believe in myself.

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