And we're supposed to believe that can track one of them?

这么说我应该相信那个玩意够追踪出？

First, they must find the arrow shaft. It will show them which tracks to follow and also who made the hit.

首先要找到箭，它指示出追踪的方向并是谁射中了猎物。

A quick survey of current diseases lets us trace out four stages in the evolution of a specialized human disease from an animal precursor.

对当前疾病的快速调查让我够追踪出从动物前身到类特殊疾病的进化的四个阶段。