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手が離せない， 手が放せない， 手がはなせない， てがはなせない
1. unable to leave the work at hand, right in the middle of something, tied up, busy
tbd
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
