When I see birches bend to left and right Across the lines of straighter darker trees, I like to think some boy's been swinging them.

当我看到白桦树弯下身子，向左，也向右,穿过排列成行的挺直黑黑的树，我总以为有个孩子把白杨“荡“弯了。

耶鲁公开课 - 现代诗歌课程节选

In just a moment the hearts are gonna start flowing from bottom to top and the cookies are gonna start moving left and right and they seem to be somewhat synchronized with the music, perhaps based on trial and error by the student who implemented this one.

刚刚那一刻，那些爱心们从底部上浮到顶部,饼干人则向左向右移动,它们似乎都随着音乐的律动而变化着，也许这是那个制作该动画的同学,不断尝试的结果。

哈佛公开课 - 计算机科学课程节选

Just looking at this first line: "When I see birches bend to left and right."

看第一句：,当我看到白桦树弯下身子，向左，也向右“

耶鲁公开课 - 现代诗歌课程节选

Then, you may have forces to the right, forces to the left pushing, pulling.

然后你就有向右的力,和向左的力,推力和拉力都有

耶鲁公开课 - 基础物理课程节选

Figure out how you can make it move a little to the left, a little to the right, up and down and then repeat in some kind of looping structure.

就是找出办法让它向左移动一小步，向右移动一小步，向上一小步，向下一小步,像这样不断重复。

哈佛公开课 - 计算机科学课程节选

When I see birches bend to left and right."

当我看到白桦树弯下身子，向左，也向右“

耶鲁公开课 - 现代诗歌课程节选

But, you know, in 2D, the options are not just left and right or north and south, but infinity of possible directions in which I could go those 5 km.

但在二维空间中,不仅可以向左向右或者向南向北,我在走那5公里的时候可以有无数个方向

耶鲁公开课 - 基础物理课程节选