嵌套

例句：

1. 1. The program is nested within the larger framework.
   这个程序被包含在更大的框架内。
2. 2. The city was designed with a series of nested neighborhoods.
   这个城市被设计成一系列嵌套的社区。
3. 3. The algorithm is nested within the main code block.
   这个算法被嵌套在主代码块内。