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speak for 代表…讲话; 为…辩护; 预定[要求]得到…; 不言而喻

"We're not blaming you," Kate said. "Speak for yourself," Boris muttered.  

“我们没有怪你，”凯特说。“也就是你这么想，”鲍里斯嘟囔道。

I speak for all 7,000 members of our organization.  

我代表本组织的7,000名成员发言。

The results speak for themselves.  

结局不言自明。

The girl was overwhelmed with emotion and couldn't speak for a moment.  

这女孩非常激动,一时说不出话来.

What have you to speak for yourself?  

你有什么话为你自己辩护 吗 ?

Have you got anyone to speak for you?  

你找到人代表你们发言了 吗 ?

Facts speak for themselves.  

事实本身就是很好的说明.

Don't speak for your friend; speak for yourself.  

不要再为人说项了, 谈谈你自己的看法吧.

Let the facts speak for themselves.  

还是让事实说话吧.

I proposed to speak for an hour.  

我想讲一小时.

She could not speak for fear.  

她吓得说不出话来.

 He said it was the job of the Church to speak for the underprivileged.  

他说，为贫困群体说话是教会的义务。

《麦克米伦词典》

Speak for yourself

used for telling someone that your opinion about something is different from theirs

这个固定习语用来告诉某人他对于某事的看法与其他人不同。可以翻译为，那只是你的看法。那只代表你个人。例如：

‘No one wants pizza again tonight.’ “今晚没人想吃披萨。”

 ‘Speak for yourself! I do!’ “那只代表你个人。我就想吃！”

从例句可以看出，A说所有的人都不想吃披萨。B不满意了，于是说了祈使句，你就说你自己吧（你代表不了我们）。祈使句的动作是还没有发生的动作，但这个祈使句使用的语境却是针对A刚才说过的话，隐含我们的想法和你是不同的这一层意思。因此翻译为那只是你的看法，那只代表你个人。并没有按祈使句直接翻译。正因为这种祈使句隐含的意思以及特殊的使用语境，词典才将这种用法当作习语而收录。普通的按正常祈使句理解的用法不属于习语或固定短语。例如，He speaks for himself. I speak for myself. They speak for themselves.都不是习语。理解上也没有特殊之处。

    speak for 用于祈使句，促使人发表见解。例如：Speak for yourself!说说你自己的意见。（摘自《薄冰英语惯用法词典》）