I can be very persuasive when I want to be.

当我想要的时候，我会很有说服力的。

《柯林斯英汉双解大词典》

He can be a real honey when he wants to be.

他高兴的时候挺招人喜欢的。

《牛津词典》

He can be very obstinate when he wants to be!

他的犟劲儿一上来，简直执拗得要命！

《牛津词典》

There used to be a time when the quickest way to travel across the western United States was in a stagecoach.

VOA: special.2010.04.26

So, at any rate, this seemed to me to be, when I started teaching this course, reasons not to teach it.

因此无论如何对我来说，当我开始教这门课的时候决定不说它的原因。

耶鲁公开课 - 现代诗歌课程节选

But the one that they do now... I would be there to see when the wrestlers come in, at the back entrance.

但是他们现在做的这种……当摔跤手进来时，我会在后门那里看着。

麦迪逊广场花园 - SpeakingMax英语口语达人

To build trust, the Panel will need to carefully manage when it needs to be transparent and when it needs to be discrete about its engagements and the advice it provides.

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So it would be great if we could have a genie who would tell us exactly when you ought to be in the stock market and when you ought to be out, but the fact is it doesn't work and if you try to do it, you're more likely to get it wrong.

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Too often, teams spend so much time figuring out what needs to be done, how it needs to be done and when it needs to be done, that they neglect to assign specific responsibility for making sure it gets done.

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