1. 勤勉地：assiduous 勤勉的 | assiduously 勤勉地 | assify 愚弄

2. 勤勉地, 恳切地：assiduous || 勤勉的, 刻苦的 | assiduously || 勤勉地, 恳切地 | assify || 愚弄

3. 勤奋地：ominously of bad omen 不吉祥地 | assiduously 勤奋地 | continuously 连续不断地

4. 刻苦地：14) modest 要求不过分的 | 15) assiduously 刻苦地 | 16) self-discipline 自我约束

adv

1. with care and persistence

e.g. she worked assiduously on the senior thesis