Language provides a means for the expression or communication of thought and in particular, as serving two major functions, namely, interpersonal communication and intrapersonal communication.

语言提供了一种表达和交流思想的工具，它尤其具有主要功能，那就是，人交流和自我交流。

Through the descriptions of the swallow,TU Fu presented his intrapersonal changes and experiences during the course of pursuing his individual political ideality and moral ideality.

杜歌中对燕子的吟诵,勾画出了他人政治理想追求和士人道德理想追求过程中的内心变化和心路历程。