So the pink line is going to move towards the vertical, and the blue line is going to move towards the horizontal, and notice that the amount of effort that we generate, goes down dramatically, goes down in this direction.

粉色的线最后会趋向垂直,蓝色的线最后会趋向水平,请大家注意下我们付出的努力,会朝这个方向大幅减少

耶鲁公开课 - 博弈论课程节选

Car is traveling with some initial speed v0 in the horizontal direction.

车以 v0 的初速度沿水平方向开出

耶鲁公开课 - 基础物理课程节选