There is no clear dividing line between what is good and what is bad.

是非之间没有明确的界限。

《牛津词典》

I draw a clear dividing line between my online and offline world.

我的网上和网下世界有一条明确的界限。

youdao

After repairing, no cracks, no hard points and no clear dividing line exist.

修补后铸件无裂纹、无硬点、无明显分界线。

youdao

There is a clear dividing line between Labor and the Liberal Democrats on the one side and the skeptical Conservative policy on Europe on the other.

VOA: standard.2010.04.23

And it has one other interesting facet a clear dividing line between good and bad performance.

FORBES: The Right Way to Measure Performance

Despite claims of unity on the crisis in the Caucasus, energy is a clear dividing line on the Continent.

CENTERFORSECURITYPOLICY: A Bear energy market

With no clear dividing line between the ownership, management, and participants in these markets, they are more prone to mismanagement and malpractices.

FORBES: Dark Pools: The Menace Of Rising Opacity In Financial Markets