complex massif

例句：

1. 1. The problem is so complex that it's hard to solve.
   这个问题太复杂了，很难解决。
2. 2. The architecture of the building is complex and requires a lot of work.
   这座建筑的构造复杂，需要大量的工作。
3. 3. The complexity of the software makes it difficult for beginners to understand.
   软件的复杂性使得初学者难以理解。