If there is a single subject guaranteed to strike fear in the hearts of parents, it is drugs.

如果只有一个话题能保证在家长们的心中引起恐惧的话，那就是毒品。

《柯林斯英汉双解大词典》

A: a topic is a chunk of information organized around a single subject.

答：主题是按单一题目范围组织的一段信息。

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Visit the library and pick up all of the books they have on a single subject.

去图书馆挑选针对一个主题的所有书。

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He believes that a study done ten years earlier by an academic researcher on a single subject could have foretold the events with TGN1412.

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Meanwhile, new specialized master's programs appeal to students, particularly those from China, eager to delve deeper into a single subject and gain a credential to compete with the growing population of educated young adults, without taking much time out of the workforce.

WSJ: Chinese Flock to the GMAT

So even though a group-granted exclusive license to a single manufacturer may be subject to antitrust scrutiny, such a license is not necessarily a violation of the Sherman Act.

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