The police had been hot on the trail of the escaped prisoners, but then the trail went cold.警方一度快要抓到逃犯，可后来却找不到他们的踪迹了。The police are hot on the trail of the escaped convicts.警方紧紧追踪着越狱犯。The police are hot on the trail of the escaped convicts. 警方在紧追逃犯。The company says it is hot on the trail of a new cancer treatment.这家公司表明即将找到一种治疗癌症的新方法。