这块木板是最厚的，厚度达5厘米。

This wooden board is the ___thickest, measuring 5 centimeters across.

这片森林里树木最茂密的地方几乎透不进阳光。

In the ___thickest part of the forest, almost no sunlight can get through.

比赛最激烈的部分持续了将近20分钟。

The ___thickest part of the competition lasted nearly 20 minutes.