I had just enough time to finish eating before the bell rang and I was off to my first class.

我在铃响前刚好有时间吃完，然后就去上第一节课了。

《柯林斯英汉双解大词典》

They (hadn't found) their books before the bell rang.

在铃响前他们仍然没有找到他们的书。

youdao

I arrived in my classroom ten minutes before the bell rang, just as the first of my students trickled in.

铃响前十分钟我提前到了教室，最早的那批学生正陆陆续续进来。

youdao

Investors were greeted by a sea of red in the commodity space Monday morning, and the selloff sunk its teeth into the equity market over the course of the day before the bell rang at session lows.

FORBES: Stocks Smacked After Commodities Crumble, Citi Skirts Market Slide

Or maybe it was more like Rocky going into the ring with Clubber Lang, unable to focus on the fight as his beloved Mick lay dying in the training room from the heart attack suffered just before the bell rang for the first round.

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In a recent interview before he rang the closing bell at Nasdaq, Sauter gave me a lengthier definition and even thanked the high-frequency traders for making the market a better place.

FORBES: Vanguard's Gus Sauter Thanks High-Frequency Traders