决心

他下定决心改变

tā xiàdìng juéxīn gǎibiàn

He is determined to change

她有很大的决心

tā yǒu hěn dà de juéxīn

She has a great determination

决心做好这件事

juéxīn zuòhǎo zhè jiàn shì

Be determined to do this well