unsolvable node

例句：

1. 1.The unsolvable node of the network is a critical issue that needs to be addressed.
   网络中的不可解节点是一个需要解决的问题。
2. 2. The software engineer struggled with the intractable node of the code.
   软件工程师在代码中遇到了难以解决的节点问题。
3. 3. The researcher found an insoluble node in the data that needed further investigation.
   研究员在数据中发现了一个不可解的节点，需要进行进一步调查。