I had cleared my desk before I left.

离开前我清理干净了办公桌。

《牛津词典》

I took the precaution of clearing out my desk before I left.

为了万全起见我离开前清理了我的桌子。

《柯林斯英汉双解大词典》

She was careful to reset the alarm before she left the office.

在离开办公室之前，她小心翼翼地重设了警报器。

《柯林斯英汉双解大词典》

A few days before she left, she gave a small American flag to her friend Jacqueline Cochran, another female pilot.

VOA: special.2010.05.26

I think that just it's a story that about his family before he left and sort of how he had a very happy, joyful life with his family.

我认为这个故事记录了,他离开日本前得家庭,以及他和家人的，快乐生活。

麻省理工公开课 - 媒体、教育、市场课程节选

It's tabulated in books, and this we can measure p in the experiment. Delta p here is the change in pressure from the left side to the right side, and we can put a thermometer, measure the temperature before the experiment and measure the temperature after the experiment.

这列在书上，这个量我们在,实验中也可以测量，在这里Δ,是从左边到右边的压强变化，我们可以放一个温度计，去测量实验前的温度,再去测量试验后的温度。

麻省理工公开课 - 热力学与动力学课程节选

Rawan has only once before left the tiny Palestinian territory, when she went on a study trip to the United States.

BBC: Gazan heads to Oxford University on unusual scholarship

Severino had never before left his territory for more than 15 days.

BBC: Brazil hunts for unique lost bird

Younus and Yousuf continued to dominate a listless visiting attack to add 113 from only 99 balls, before left-arm spinner Ray Price had both caught in the deep off extravagant shots.

BBC: Jamshed impresses in Pakistan win