(英翻中) 這句話這樣翻譯對嗎?

不知道這樣翻順不順?
Part of being a winner is knowing when enough is enough.
(成為贏家是明白何時適可而止)
Sometimes you have to give up the fight and walk away,
(有時你們必需放棄戰鬥)
and move on to something that's more productive.”
(然後繼續做些有建設性的事....)
By Donald Trump唐納·川普
請問
1.為什麼用part of?
2.and move on to something that's more productive.”
為什麼不用and move on to do something ...............