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祖父， そふ， じじ， じい， おおじ， おじ， そぶ
1. grandfather
2. old man
3. kyogen mask used for the role of an old man
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
