topics
A topic is a particular subject that you discuss, study, or write about.
The weather is a constant topic of conversation in Alaska.
在阿拉斯加,天气是一个永恒的交谈话题。
The main topic for discussion is political union.
讨论的主题是政治联盟。
This topic is explored more fully in chapter 5.
第五章更完整地探讨了这个主题。