1、 Half of the students in four large philosophy classes read an article on the ethics of factory-farmed meat, optionally watched an 11-minute video on the topic and joined a 50-minute discussion.
在四节大型哲学课上，一半学生阅读了一篇关于工厂化养殖肉类的伦理文章，非强制性观看了一段11分钟的视频，并开展了50分钟的讨论。
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2、 Optionally enter a type.
可以选择输入一个类型。
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