expand tubes

例句：

1. 1. The company plans to expand its operations in the new market.
   该公司计划在新的市场中扩展其业务。
2. 2.The population is expected to expand as more people move to the city.
   随着更多人搬到城市，预计人口将会增加。
3. 3. The team expanded their knowledge of the subject by reading additional research papers.
   通过阅读额外的研究论文，团队扩大了对主题的了解。