用尽全部力气换一声叹息
[yòng jĭn quán bù lì qì huàn yī shēng tàn xī]
'Yong Jin Quan Bu Li Qi Huan Yi Sheng Tan Xi' literally translates to 'Using All Strength to Exchange a Sigh'. It shows the hopelessness and disappointment after exhausting every effort, implying giving out all just only receive little return.