不遺餘力

to spare no pains or effort (idiom); to do one's utmost

no; not so / (bound form) not; un-

to lose / to leave behind / to omit / to bequeath / sth lost / involuntary discharge (of urine etc)

(bound form) to leave behind

extra / surplus / remaining / remainder after division / (following numerical value) or more / in excess of (some number) / residue (math.) / after / I / me

surname Yu

variant of 餘|余[yu2], remainder

energy left over (to do sth else)

power / force / strength / ability / strenuously