"The farmer is handsome."
Translation:Uʻi ka mahiʻai.
I would think that nohea is a better descriptor. U'i implies young and beautiful. Nohea implies handsome, though very similar. Nani does not necessarily imply young, merely pretty.
My understanding of the grammar goes like this: for an English sentence such as: "A is B," the Hawaiian sentence becomes "B A." This makes it a complete sentence.
In this sentence "A" is "the farmer" (ka mahiʻai) and "B" is "handsome" (uʻi). So "the farmer is handsome" becomes "uʻi ka mahiʻai."