犀牛牌安宫牛黄丸:favor与favour的区别，为什么所有的书里全是Could you do me a favor?而没有Could you do me a favour?

favor 是美语
favour 是英式英语

没有区别，随便用

favor是美式英语，favour是英式英语。也许书本印刷时比较倾向美式英语。

没什么区别，英式英语比较传统，写作favour，而美国人追求简洁，所以简化了一下。类似的词还有color，英式是colour而美式是color.

至于你说could you do me a favour，可能课本上是这样的，因为我们学习的大都是英式的英语。写成could you do me a favor也完全正确。

一样的
就像颜色：color<美>=colour<英>

favor: [ 'feivə ]

n. 好意,喜爱
v. 支持,喜欢,证实

例句与用法:
1. He did all he could to win his favor.
他尽其所能去赢得他的好感。

2. A mother mustn't favor one of her children more than the others.
母亲不应对任何一个儿女有所偏爱。

3. Public opinion was moving strongly in favor of disarmament.
公众舆论正在强烈支持裁军。

4. One that enjoys special favor or regard.
受宠的人或物受到特别喜爱或对待的人或物

5. In their discussion, I was in favor of Mr. Li.
在他们的争论中, 我支持李先生。

6. Would you do me a favor?
你能帮我一个忙吗？

7. That might be in your favor.
那可能对你有利。

8. Could you do me a big favor?
能否请你帮我个忙？

favour: [ 'feivə ]

n. 帮助(促进,好感,证实,来信,礼物)
vt 促进

例句与用法:
1. Cheques should be written in favour of Oxfam.
支票上请写明以牛津饥荒救济委员会为受款人。

2. Of the two possible plans I favour the first.
在这两种可行方案中我赞成前者.

3. Everyone at the rally wore red ribbons as favours.
参加集会的人都系著红丝带作为支持大会的标记.

4. The wind favoured their sailing at dawn.
这风便於他们在黎明时航行.

5. The decision went in his favour.
这一判决对他有利.

6. The court decided in his favour.
法庭的判决对他有利.

7. She always favours her youngest child (more than the others).
她总是偏爱她最小的孩子.

8. May I ask a favour of you (ie ask you to do sth for me)?
请您帮个忙行吗?