Light emitted in this environment will have a certain frequency, which is related to the time scale (or the gravity strength) of the environment.

在那样环境下所发射的光会具有一定的频率，这个频率是与环境的时间标度(或引力强度)有关。

youdao

Some beginner runners are actually physically fit enough to run a certain distance, but they don't have the confidence or mental strength to push themselves farther.

一些新手其实身体上足够适合跑一段距离的，但是他们没有信心或精神力量来促使他们跑的更远。

youdao

So in the beginning itself also needs to have certain economic strength to deal with future business what is happening in the unpredictable things!

所以在创业初期自己也需要有一定的经济实力才可以应对未来创业中所发生的一切不可预料的事情！

youdao

It's - a suture or a stitch has to hold the wound closed so it has to have certain mechanical strength and imagine the problem of making something that's dissolvable so it disappears but also is strong enough to hold a wound closed reliably for a length of time.

能够拉紧切口的缝合线,就必须具有一定的机械张力,大家想像一下制造这种缝合线的难度,身体组织不仅要能吸收这种缝合线,而且这种线必须有足够的张力,一定时间内能够拉紧切口

耶鲁公开课 - 生物医学工程探索课程节选

However, since 2007, dietary supplement manufacturers are required to follow certain guidelines to ensure they're pure, have a consistent strength and are manufactured appropriately.

WSJ: Vitamins Become Growing Business for Consumer-Product Companies