医生们之所以不能向病人提供确切的预后，不仅仅是因为他们做不到。

The reason doctors don't give patients specific prognoses is not merely because they cannot.

youdao

四不要：不要试图叫抑郁症患者振作，因为他们做不到，他们的状况身不由己。

Do not: Do not try to cheer called depression, because they can not, their situation involuntarily.

youdao

他们都遇到了很大的问题，就是她们都做不到，因为树枝和果实每次都移动开了。

They both took great trouble, but they were not able to do it, for the branches and fruit both moved away from them every time.

youdao

The British Government will never promise to pay you 10% more each year because they can't do it.

英国政府永远都不会承诺给你们,每年支付你们高于10%的利息,因为他们根本就做不到

耶鲁公开课 - 金融市场课程节选