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勢い， 勢， いきおい， いきよい
1. force, vigor, vigour, energy, spirit, life
2. influence, authority, power, might
3. impetus, momentum, course (of events)
4. naturally, necessarily
力量、活力、精力、能量、精神、生命；影响、权威、权力、威力；冲力、势头、事件的发展进程；当然地，必然地
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衰える， おとろえる
1. to become weak, to decline, to wear, to abate, to decay, to wither, to waste away
tbd
の
1. indicates possessive
2. nominalizes verbs and adjectives
3. substitutes for "ga" in subordinate phrases
4. (at sentence-end, falling tone) indicates a confident conclusion
5. (at sentence-end) indicates emotional emphasis
6. (at sentence-end, risi...
句尾起强调作用；助词，表示所有关系
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
