complex structure

例句：

1. 1. The architecture of the building is complex and requires careful planning.
   这座建筑的建筑结构复杂，需要仔细规划。
2. 2.The problem is so complex that it's hard to solve.
   这个问题太复杂了，很难解决。
3. 3. The story is complex, with many twists and turns.
   这个故事很复杂，有很多曲折。