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人类的生存无时无刻不在受到来自自身和外部危险的威胁。6500万年前,一颗小行星击中了地球,毁灭了恐龙;那么人类会不会重蹈复辙?
Human life is constantly threatened by its own and external dangers. 65 million years ago, an asteroid hit the Earth, destroying the dinosaurs; then humans will not repeat the same mistake?