侦探发现从窗户向外延伸的泥泞足迹。

The detectives found muddy ___tracks leading away from the window.

我们顺着动物在新雪中留下的足迹前进。

We followed the animal's ___tracks through the fresh snow.

那辆车在沙漠松软的沙地上留下了深深的车辙印。

The vehicle left deep ___tracks in the soft sand of the desert.