The need to communicate is a key characteristic of human society. 需要交流是人类社会最重要的一个特征。Scientists conti
The need to communicate is a key characteristic of human society.
需要交流是人类社会最重要的一个特征。
Scientists continue to push back the boundaries of human knowledge.
科学家不断扩大人类知识的范围。
The cost in terms of human life was high.
付出了很大的生命代价。
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