见义勇为。用英语怎么说？

见义勇为。

Do boldly what is righteous.

do

aux. 构成疑问句和否定句，代替动词，用于加强语气；vt. 做，干，进行，从事；vi. 表现，进展，引起，行过；n. 社交聚会，社交活动，宴会；

例句
Rachel was going to do something about Jacob...
蕾切尔将对雅各布有所行动。

boldly

adv. 大胆地，显眼地，冒；

例句
In answer to speculation that she wouldn't finish the race, she boldly declared her intention of winning it.
为了回应她会中途退赛的猜测，她大胆地宣布她要赢得这场比赛。

what

pron. （用以询问某人或某事物的词）什么，多少，…的事物；adj. …的（事物或人）；adv. （用于感叹句中）；int. （用以表示不相信或惊奇），（用以表示未听清楚对方说的话）；

例句
How big is the abyss between what you think you are and what you actually are?
你对自己的认识和真实的你之间差别到底有多大？

is

vt.& vi. 是（be的三单形式；n. 存在；

例句
Bollinger 'RD' is a rare, highly prized wine.
博林格RD香槟是一种名贵的备受推崇的葡萄酒。

righteous

adj. 正直的，正义的，公正的；

例句
...the righteous struggle between decency and depravity.
在高尚和堕落之间的道德挣扎