break one's back

Từ điển Oxford Learners Wordfinder Dictionary

verb

work very hard, like a slave (Freq. 1)
• Syn:
slave, buckle down, knuckle down
• Derivationally related forms:
slave (for: slave), slavery (for: slave)
• Hypernyms:
work, do work
• Verb Frames:
- Somebody ----s