zest

他以极大的热情投入到这个新项目中。

He tackled the new project with great ___zest.

她的幽默感为派对增添了不少乐趣。

Her sense of humor added a lot of ___zest to the party.

制作柠檬蛋糕前，你需要先擦柠檬皮。

Before making the lemon cake, you need to ___zest the lemon first.