a good turn

基本解释

You thought I was too little to do you a good turn. But see, you owe your life to a poor little mouse.
你以为我太小了不能行善报答你，但是，你瞧，全亏可怜的小老鼠你才拣条命。
Whoever figured out that a scoop of ice cream was meant to float in a glass of fizzy soda did his fellow man a good turn.
把一勺冰淇淋放入一杯冒泡的汽水中，不管是谁制造出这样一杯饮料给他的朋友，表现出的是一种友善。
You also can e-mail the irritating kid your notes, and, in the college bartering system, now he owes you a good turn if you ever happen to miss class yourself.
您还可以把你的笔记电邮给那个让人崩溃的小子，并且，在大学以物易物的制度下，现在他欠你一个人情，如果你碰巧缺课。

It didn't turn out well, but you know, I mean it was a nice memory though, a good experience making chocolate."
And in a moment I'll turn to evaluate whether it's a good argument or not, but I think it's a pretty interesting argument.
一会儿我会评估,这是不是个好的论证,但是我认为这是个很有趣的论证。
耶鲁公开课 - 死亡课程节选
I don't think that's a very good reason because you choose to- either way you have to choose who dies because you either choose to turn and kill the person, which is an act of conscious thought to turn, or you choose to push the fat man over which is also an active, conscious action.
我认为这不是一个很好的理由,因为不论哪种情况，你都得选择让谁死,或者你是选择转弯撞死一名工人，这种转弯就是种有意识的行为，或者你是选择把胖子推下去,这同样是一种主动的，有意识的行为。
耶鲁公开课 - 公正课程节选

My answer is this: he was trying to do that short devil a good turn.
NPR: Excerpt: 'True Grit'