I am sure you all know from physics class about how light moves in microscopic ways and that we can only see light when the wavelength of that light is in a specific range.

我相信，你们在物理课上都学过光是如何以微观的方式运动的，以及只有在光的波长在特定的范围内时我们才能看到光这一事实。

youdao

Only when all of us join efforts to eliminate pollution at all levels can we expect to have a better environment.

只有当我们所有人共同努力消除各种污染时，我们才能期望有一个更好的环境。

youdao

Only when we react to emergencies in life calmly, can we solve problems in a better way.

只有当我们冷静应对紧急状况时，我们才能更好地解决问题。

youdao

And when monkeys can't give us the answers we need,only then, do we move to the chimpanzee."

VOA: standard.2010.02.16

It was only when we started to study those that we actually understood how we can best help that population.

只有当我们开始研究这些,才能了解如何帮助到整体。

哈佛公开课 - 幸福课课程节选

We can't stand against them anymore and when you start running, the only thing the guys who are left up front can do is run.

我们打不过他们了,而你开始逃跑,留在前面的人唯一能做的也是逃跑

耶鲁公开课 - 古希腊历史简介课程节选

Only when we can identify and eliminate these barriers can we truly unleash the full potential these women have to drive economic growth worldwide.

FORBES: A Breakthrough Initiative to Advance Women and the World

Only when we are armed with knowledge can we effectively reduce further transmission and save the lives of our loved ones living with Hepatitis B.

WHITEHOUSE: Hepatitis B and the AAPI Community

We can only influence them when we prove to them that we are doing the right thing.

NPR: Infighting Marks Sunni Political Efforts in Iraq