1. The disk, which is composed of continuous annuluses, can expand equivalent triangle by asymptotic e line. We can obtain the circular area which is visually expressed by circumference and radius. 把紧密相连的圆环构成的圆盘以渐开线展开成等面积的直角三角形，得出了较为直观的由周长和半径表示的圆面积公式。
2. It has also been seeking to expand its investments in Africa by developing oilfields in Angola, Nigeria and Sudan. 该公司还试图通过开发安哥拉、尼日利亚和苏丹的油田，扩大自己在非洲的投资。
3. Albumin can quickly expand fluid and maintain a stable plasma colloid osmotic pressure in patients with hypovolemia. 白蛋白对低血容量患者可迅速扩容，并能维持稳定的血浆胶体渗透压。
4. Note that the magnetic forces act to compress axially (lengthways) and expand radially (outwards). 注意到，该磁部队法，以压缩轴向（纵向），并扩大呈辐射状（向外）。
5. The final purpose of solving judicial almsgiving is to expand the meaning and extension of the rights to litigate. 解决人权的司法救济最终性，主要应当扩展诉权的内涵和处延。
