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かどうか
1. whether or not (in phrases like "I don't know whether or not I can come")
是否、能否(在诸如“我不知道自己是否能来”这样的表述中)
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疑わしい， うたがわしい
1. doubtful, questionable, uncertain, disputable, suspicious
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
