The twins are so alike that I can't tell one from the other.

那对双胞胎太像了以致我不能把他们区分开。

beike.dangzhi.com

The twin brothers are so alike that I cannot tell one from the other.

这对孪生兄弟长得像极了，我无法分辨。

dict.cn

The twins are so much alike that it's impossible to tell one from the other.

这对双胞胎非常相像，几乎不可能把他们分辨出来。

www.cbe21.com

All right, so I need to tell you the path, when I go from one state to the other.

好，当我从一个状态过渡到另一个状态时，我需要告诉你们路径。

麻省理工公开课 - 热力学与动力学课程节选

Well, how can you tell the one from the other?

那么你怎么把它们分开呢？

耶鲁公开课 - 文学理论导论课程节选

And while there is many a newspaper or magazine editor who dreams of unearthing that freelance gem he truly believes is out there, most of the young (and not so young) hopefuls that phone constantly and fill his inbox cannot tell one end of a story from the other.

ECONOMIST: A journalistic problem solved?

And because there is no way to tell a Klamath-spawned salmon from one from any other river once the fish reach the ocean, the fishery council says it has no choice but to restrict all salmon fishing along 700 miles of coast.

ECONOMIST: Saving the fish of the Klamath river

Outside economists will tell you -- not adjuncts of one party or the other, or people from partisan think tanks -- but economists on Wall Street, economists out in the country, and academic economists who are not affiliated with a party or a position, will tell you that a payroll tax cut has a measurable, direct, positive impact on the economy.

WHITEHOUSE: Press Briefing