complex acid

例句：

1. 1. The problem is complex and requires a detailed analysis.
   这个问题很复杂，需要详细的分析。
2. 2.The architecture of the building is complex and requires careful construction.
   这栋建筑的建筑结构复杂，需要仔细建造。
3. 3. The solution to this problem is complex and requires a deep understanding of the underlying principles.
   解决这个问题的方法是复杂的，需要深入了解其背后的原理。