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硬い， 固い， 堅い， 緊い， かたい
1. hard, solid, tough
2. stiff, tight, wooden, unpolished (e.g. writing)
3. strong, firm (not viscous or easily moved)
4. safe, steady, honest, steadfast
5. obstinate, stubborn
6. bookish, formal, stuffy
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
と
1. if, when
2. and
3. with
4. used for quoting (thoughts, speech, etc.)
5. promoted pawn
6. indicates a question
表示引用
