Acceleration and velocity are both vectors.加速度和速度都是矢量。the velocity of light光速Einstein's theory links energy with mass and velocity of light.爱因斯坦的理论把能量同质量和光速联系起来....
They make no secret of their leftist sympathies.他们毫不掩饰自己对左派的同情。Activists pasted up posters criticizing the leftist leaders.激进分子张贴起海报批评左翼领袖。In return, they are themselves accused of furthering their own (leftist) politica...