To develop or increase in stages or by degrees:扩大，集结，支持：逐步或分阶段的发展或增加：built up the business; building up my endurance for the marathon.扩大企业；为跑马拉松而增强我的耐力
To accumulate or collect:积累或收集：sediment building up on the ocean floor.海底积累的沉积物
To bolster:支持，增加，树立：build up the product with a massive ad campaign; built up my hopes after the interview.通过大量的广告活动来树立这种产品；在面试后增加我的希望