mirthfully

例句：

1. 1.She laughed mirthfully at the joke.
   她开心地笑了。
2. 2. The children played happily in the park.
   孩子们在公园里快乐地玩耍。
3. 3.He sang mirthfully to celebrate his birthday.
   他开心地唱歌庆祝生日。