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いまいち， イマイチ， 今一， 今いち
1. not quite (right), not very good, somewhat (lacking)
tbd
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信用できる， 信用出来る， しんようできる
1. to be trustworthy, to be credible, to be believable
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
