I think this sentence means that humans and animals live in beautiful, endless, and cruel world. I feel this sentence "この美しい果てしない残酷な世界では人間と動物が生きてる" is strange as Japanese. I think "この美しい果てしない残酷な世界で、人間と動物が生きている" is more natural.
@andreaitagamer I think you are right. 誰は誰か？is who is who. This is correct in grammar, but it is no meaning. If I translate something, I need to think original sentence intend to express, but original sentence '誰は誰か' is difficult to understand for me (Japanese native speaker). I can say your understanding level is as same as me in this case.
The Language Level symbol shows a user's proficiency in the languages they're interested in. Setting your Language Level helps other users provide you with answers that aren't too complex or too simple.
Has difficulty understanding even short answers in this language.
Can ask simple questions and can understand simple answers.
Can ask all types of general questions and can understand longer answers.
Can understand long, complex answers.
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