我加了点面粉，让汤变得浓稠些。

I added some flour to make the soup ___thicker.

汤煮的时间越长，它就会变得越浓稠。

The soup ___thickened the longer it was cooked.

随着更多证人的出现，案情变得更加复杂了。

The case ___thickened as more witnesses came forward.