Communication with network can make students contact. with more people, and improve expressing ability.

利用网络进行交流，能扩大学生的接触面，提高学生的英语表达能力。

The data-independent multi-branch tree hierarchical structure is proposed for the knowledge representation, because it has strong expressing ability and can be easily expanded.

此外还提出了与数据无关的多叉树层次结构模型的知识表示方法，它具有很强的表达能力并易于扩展。