1. 边界：border marquee 边框圈选 | bounds 边界 | break apart 打散
2. 边缘：比赛,竞赛: game, match, competition, contest, tournament, chal... | 边缘: edge, limit, margin, threshold, boundary, bounds, border, frontier, verge | 病: illness, disorder, disease, sickness, ailment, ...
3. 桅肩：bounding bar 界边角钢 | bounds 桅肩 | bounties 出口奖励金
4. 限制：Bounds 限制︰limits | Chance 偶然的︰unplanned | Integral 必要的,基本的︰an essential