Sniffer dogs could be trained to track them down.

可以训练嗅探犬来追捕他们。

《柯林斯英汉双解大词典》

It is thought that the train hit a boulder that had fallen down a cliff on to the track.

人们认为这列火车撞到了从悬崖滚到铁轨上的大圆石。

《柯林斯英汉双解大词典》

The police have so far failed to track down the attacker.

警方至今未能追捕到攻击者。

《牛津词典》

In recent days, there have been reports that the Internet search company Google has turned to the U.S.intelligence community to help track down threats to its operations in China.

VOA: standard.2010.02.07

"But our view is, there is still time for diplomacy and,I might say, sanctions to persuade the Iranians that their security will be diminished by going down the track of nuclear weapons."

VOA: standard.2009.09.17

Paul Martin Smithers, 59, skipped bail in 2000 and it took almost a decade to track him down to south east Asia.

BBC: Parc Prison

The second phase will be to track down the militants to their desert hideouts, which could prove a much more difficult task, he adds.

BBC: Mali crisis: French-led troops 'surround Timbuktu'

The apparently Chinese cybercriminals are using Google searches to track down sites vulnerable to so-called "SQL injections, " says Jeremiah Grossman, chief technology officer of security firm Whitehat Security.

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