The formula is jealously guarded.

对该配方戒备森严。

《柯林斯英汉双解大词典》

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There's a good explanation for the phenomenon in the book The Formula: The Universal Law of Success by Albert Laszlo Barabasi.

阿尔伯特·拉兹洛·巴拉巴斯（Albert Laszlo Barabasi）所著的《公式：成功的普遍法则》（the Formula: the Universal Law of Success）一书对这一现象作出了很好的解释。

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The race car meets all of the Formula Three racing requirements except for its biodiesel engine.

VOA: special.2009.11.03

And we can calculate that with the formula that we used, which was just n minus l minus 1 equals the number of nodes.

这个我们可以用我们以前用过的那个公式来计算，也就是节点数等于ｎ减去ｌ减去１

麻省理工公开课 - 化学原理课程节选

The formula tells us or absorbed based on the energy difference between the two levels that we're going between, that the electron is transitioning between.

这些公式告诉我们,或发出的光的，频率大小,是基于，电子转移的，两个能级，之间的能量差。

麻省理工公开课 - 化学原理课程节选

Lord Barnett said it was not a tribute to the formula that it has lasted so long.

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For those New Yorkers, the formula seemed to provide faster and more reliable awards.

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Our new racing bike, the Venge, was codesigned with McLaren, the Formula One team.

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