它往往具有较大的规模，而且有一个明确的主题。

It often has a larger scale and a clear theme.

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用明确的主题，人们很忙，通过看主题，告诉他们什么是重要的，需要首先处理。

People are extremely busy. By being able to scan the subject lines, it tells them what is important and needs to be addressed first. Keeping your emails short also helps with this.

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持久性和慢性病毒感染，一些人类疾病的相关性有明确的主题，会谈将涉及在晚上的会议。

Talks on persistent and chronic viral infections, a topic with clear relevance to a number of human diseases, will be covered in the evening session.

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