Tā yǐ jídà de rèchén tóurù dào zhìyuàn fúwù zhōng.
He threw himself into volunteer service with great zeal.
Tips
usage
热忱 (literary/formal) and 热情 (colloquial) both mean enthusiasm, but 热忱 has a warmer, more sincere connotation — a deep-felt passion — while 热情 can apply to more surface-level warmth.
