cheerfulness 

英汉解释

n. 高兴；快活

同义词

n. blitheness，cheer，sunniness，sunshine

反义词

n.   cheerlessness，uncheerfulness

参考例句

1. Cheerfulness is the promoter of health.
心情愉快是健康的促进剂。
2. Cheerfulness is the basis of friendliness.
令人愉快是友谊的基石。
3. May everything beautiful and best be condensed into this card. I sincerely wish you happiness , cheerfulness and success.
原一切最美好的祝福都能有这张贺卡表达，真诚地祝愿你幸福，快乐，成功！

英英解释

n.
  1. the quality of being cheerful and dispelling gloom
  2. a feeling of spontaneous good spirits

网络释义

cheerfulness
快乐，高兴，愉快; 高兴; 甘心; 意气风发;
Cheerfulness is health
欢乐就是健康，忧郁就是病痛。;
cheerfulness jauntiness liveliness merriness sprightliness
快活;
assume an air of cheerfulness
假装高兴的样子;
cheerfulness and sense of humor
乐观和幽默感;