cheerfulness

Her natural cheerfulness acted as a tonic for the rest of the weary team during the long meeting.

(Chinese) 在漫长的会议期间，她天生的快乐性格对疲惫的小组其他成员起到了提神作用。

The bright colors and natural light in the ward were designed to promote cheerfulness among the patients.

(Chinese) 病房里明亮的色彩和自然光旨在提升患者的愉快心情。