This is the 11856th most frequent German word.
thun
"Thun" is an archaic German spelling of "tun," which means "to do."
The term 'thun' here is used in the sense of 'to do', indicating an action that needed to be performed. It is an old-fashioned spelling of 'tun' used in historical or stylistic contexts.
Er wusste nicht, was zu thun war.
He didn't know what was to be done.
In this example, 'thun' reflects an action of doing, suggesting a recommendation or suggestion of an action. Again, 'thun' is an older spelling used occasionally for stylistic purposes.
Das Beste, was du thun kannst, ist, ruhig zu bleiben.
The best you can do is to stay calm.
Here, 'thun' represents the concept of action or performing something. It demonstrates its use in a hypothetical or retrospective scenario. This spelling reflects its traditional variation.