trace 
英 [treɪs]  美 [treɪs] 
n. 痕迹；踪迹；微量；迹线

v. 追溯；回溯；跟踪，追踪；描绘；探索；沿路走

例句：
All trace of blood on the floor had gone. 

地板上所有的血迹都不见了。

There was no trace of the robbers. 

根本没有劫匪的踪影。

Finally, and mysteriously, Hoffa disappeared without trace. 

最后，霍法毫无踪迹地神秘消失了。

Neither of them showed any trace of alcohol in their blood. 

他们俩的血液中一点儿酒精也没有。

Wash them in cold water to remove all traces of sand. 

用冷水冲洗它们以清除所有的沙子。