n. 无忧无虑；自由自在；轻松愉快
the cheerful feeling you have when nothing is troubling you
同义词： carefreeness / insouciance / lightsomeness
lighthearted 快乐的，心情愉快的；无忧无虑的
lightly 轻轻地；轻松地；容易地；不费力地
lightening 孕腹轻松
lightness 轻盈；轻松；明亮；（颜色）浅淡
lightening 减轻（lighten的ing形式）；闪电；发光
lighten 减轻；发亮
lighten 使照亮；使轻松
无忧无虑；自由自在；轻松愉快
This apparent lightheartedness does not conceal the real contempt that many men feel for women.
可这表面现象却无法掩饰许多男人对女性所抱的鄙视态度。
Solemnity and lightheartedness, an important dimension of Chinese literature, has been subjected to an undeserved negligence.
严肃与轻松作为解读中国现代文学史的一个重要维度，长期以来受到学界不应有的忽视。
Pink roses: elegance, gracefulness, refinement, gentility, style and poetic romance but being combined with fun and lightheartedness.
粉红玫瑰：高雅，优雅，精致，温婉，风格和诗意浪漫，但又结合乐趣和轻松愉快。
Alexandre Desplat, The Queen: A score with many levels manages the movie's transitions between pomp and lightheartedness.
He used humor and lightheartedness to project optimism and to distinguish himself from the earnest even moralizing voice of Jimmy Carter.