The artist must be a bridge between the visible and the invisible.
I don't care what you say about me as long as it's not true.
关系模型基于谓词逻辑和集合论,为数据库管理提供了坚实的数学基础。
光波,无论是以太波还是其他波,在所有情况下都是时间上的周期性过程。