The vote was seen as a major setback for Mr.Topolanek as it came just days before a planned visit by United States President Barack Obama and midway through the rotation of the Czech Republic's European Union presidency.

VOA: standard.2009.03.25

The idea that he had was, if you go from me to you, with a clockwise rotation, you go from you to me by a counterclockwise rotation.

他的方法是这样的,如果这个矢量从这转到那是顺时针方向,那么这个矢量转回来就是逆时针方向

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