I think we're on the trail of several crimes.

我认为我们在查的是连环犯罪。

It was clear to me that you were on the trail of Slytherin's heir.

我看得出来，你在寻找斯莱特林的继承人。

Today, I'm on the trail of a T-Rex, tomorrow I'm tracking a Stegosaurus.

目前，我在追踪一只霸王龙，明天，我又去追踪剑龙。

The mother bear is on the trail of a herd of deer, but the deer are also wise to predators.

熊妈妈在追踪一群鹿，但鹿也会很机敏地对付掠食者。

Instead, I'm on the trail of clues left by dinosaurs and other extinct animals when they were active and very much alive.

而是寻找恐龙和其他已灭绝动物存活时留下的痕迹。