If he wins—and it's a big if —he'll be the first Englishman to win for fifty years.

假设他赢了—不过这还是个很大的疑问—他将成为五十年以来第一个获胜的英格兰人。

《牛津词典》

Of course all of this is a big if.

当然这一切都基于一个很大的假设。

youdao

That, however, is a big if.

不过，这只是一个大方向的设想。

youdao

He is a leader in the sign-making industry - a real big gun,if you know what I mean.

VOA: special.2010.11.28

Of course,that's a big if.

当然这个，如果，是很难实现的。

耶鲁公开课 - 死亡课程节选

or if you're feeling like a big event has happened. Or if you're feeling that they look really great.

或者你觉得对方发生了什么大事，或者是你觉得他们看起来棒极了。

You look 课堂 - SpeakingMax英语口语达人

Given the high prices of rare disease drugs, sales could be big if enough patients can be found.

FORBES: Biotech's Worst Winner of 2012

That's a big if--and it masks a series of troubling decisions the founders have made almost since the beginning.

FORBES: Gold Diggers

If that has changed - and that is a big if - then the pound could well fall in 2013.

BBC: A pounding for sterling in 2013?