1、The police traced the call to her ex-husband's number.警方用追踪装置查出是她前夫的电话号码打出的电话。
2、The research effort has focused on tracing the effects of growing levels of five compounds.研究重点追踪了5种化合物含量上升的影响。
3、Analysis showed that traces of arsenic were present in the body.分析显示，尸体中有微量砒霜。
