n.先驱，前导；（尤指经新陈代谢形成另一种物质的）前体，前质；前兆
precursors───n.前体细胞（precursor的复数）；先驱者（precursor的复数）
precursory───adj.前兆的（等于precursive）；先驱的
precensor───vt.事先审查
precurrer───前辈
precurse───n.预示，征兆；v.预示，征兆
precursed───n.预示，征兆；v.预示，征兆
precurses───n.预示，征兆；v.预示，征兆
percursory───感知的
precensors───vt.事先审查
Error is often the precursor of what is correct.───错误常常是正确的先导。
He said that the deal should not be seen as a precursor to a merger.───他说这次交易不应该被看作是合并的前兆。
We talked about the artificial hip, which is a modern precursor of the splint I talked about before.───我们说到的人造髋关节就是我之前讲过的夹板的现代前身。
Thus it appears that any variability whatsoever in background seismicity can be claimed, after the fact, to have been a precursor.───这样看来，可以将背景地震活动性中的任何变化，在地震发生之后，认为是一种前兆。
I mean it wasn't terrible, it was sort of a precursor to what people are trying to do It flopped miserably, but I'm glad we did it.───其实也没那么糟糕，它就是个先兆，预示了现今人们，很悲惨它失败了，不过我很高兴我们做过。
To be able to use their equipment, at least one team member must know how to adapt Precursor technologies.───要使用先行者的装备，至少要有一个队伍成员知道如何适应先行者科技。
Impatience is often a precursor to self-punishment, so stop way before the red light hits.───焦躁通常是自我惩罚的前兆，因此，你得赶快在红灯亮起之前停下来。
The ADP report is often seen as a precursor to the Labor Department's big monthly jobs report due out Friday.───ADP就业报告被看做美国劳工部将于周五公布月度就业报告的预兆。
Error is often the precursor of what is correct, but conceit is the prelude to a fall.───错误往往是正确的先导，骄傲是跌跤的前奏。