translation.en: Now, if you're playing doubles, then the person on your side of the net is in a non-zero-sum relationship with you, because every point is either good for both of you -- positive, win-win -- or bad for both of you, it's lose-lose.
translation.zh: 现在，如果你玩双打， 那么在你网子这边的人 与你就是非零和的关系。 因为每一分不是对你们俩同时都是好的，积极的，双赢， 就是对你们两个同时都是坏的，双输。好。