Preach by practice.

用实践来证明。

youdao

Theory must be demonstrated by practice.

理论必须通过实验验证。

youdao

And the only way they can get there is by practice.

要想达到他的境界唯一的办法就是实践。

youdao

Nowak is very critical of the widespread use of this practice by the former Bush administration.

VOA: standard.2009.03.21

Why does he go against the traditional Ancient Near Eastern practice of primogeniture, inheritance by the first born?

为什么他要违背传统古代近东的惯例,也就是长子继承制，由第一个儿子继承？

耶鲁公开课 - 旧约导论课程节选

He would also regard the peculiar American practice of elections rather than the Greek practice of appointing political offices by lot.

他也将关注,奇怪的美式选举方式,那有别于透过抽签决定的,希腊式指派政治官位模式。

耶鲁公开课 - 政治哲学导论课程节选

Sometimes these funds are only socially responsible by name instead of by practice, Lowlicht says.

FORBES: Intelligent Investing Panel

The knowledge required for raising castells is traditionally passed down from generation to generation within a group, and can only be learned by practice.

UNESCO: Intangible Cultural Heritage

But as the report makes clear, the gap between policy decided by senior officers and practice by junior officers on the streets is all too wide.

ECONOMIST: A tragedy and a shame