cheerfulness
  高興,快活
  Cheer·ful·ness, n. Good spirits; a state of moderate joy or gayety; alacrity.
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  cheerfulness
       n 1: the quality of being cheerful and dispelling gloom; "flowers
            added a note of cheerfulness to the drab room" [syn: cheer]
            [ant: uncheerfulness]
       2: a feeling of spontaneous good spirits; "his cheerfulness
          made everyone feel better" [syn: blitheness] [ant: cheerlessness]