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いる， 要る
1. to be needed, to be necessary, to be required, to be wanted, to need, to want
被需要，不可或缺，被要求，被想要，需要，想要
は
1. indicates sentence topic
2. indicates contrast with another option (stated or unstated)
3. adds emphasis
指示句子的主题；表示与另一选项（无论是否明确提及）形成对比；表示强调
