ardor
他带着极大的热情投入到新的项目中。
He approached the new project with great ___ardor.
这位年轻的钢琴家以不倦的热忱反复练习那段困难的乐句，直到天亮。
The young pianist practiced the difficult passage with relentless ___ardor, repeating it until dawn.
她以极大的热忱推动环保事业，招募了数百名志愿者。
She championed the environmental cause with an ___ardor that recruited hundreds of volunteers.