Once he's made up his mind, he never budges / you can never budge him ( from his opinion ).他一旦下了决心就毫不动摇[无法使他改变 ( 意见 ) ]....

budges的音标：...

v.（使）稍微移动( budge的第三人称单数 )，（使）改变主意，（使）让步...