火车头排出的煤烟在车站建筑上留下了一层厚厚的污垢。

The locomotive left heavy ___soot on the station building from its smoke.

农民们担心玉米会感染黑穗病。

The farmers are worried that the corn might get infected with ___smuts.

这部电影因含有大量低俗内容而被限制上映。

This movie was restricted for containing too much ___smut.