Suggestions(1)
The phrase 'the prettier' is correct and usable in written English.
It is typically used as an adjective to describe something that is more attractive than something else. For example: "Between those two dresses, I like the prettier one with the pink flowers."
Dictionary
the prettier
adverb
Somewhat, fairly, quite; sometimes also (by meiosis) very.
Exact(60)
The prettier child is stimulated saliva.
The prettier scenery has it price though.
"It's the prettier version," he says.
Roy is the prettier but less likable of the two.
The prettier one also seemed to be the more conventional.
In some of the prettier valleys, interior decorators are more common than ranch hands.
As I shopped, it became obvious that the prettier the garment, the less control it had.
He sang many of the prettier passages with his head craning upward and his eyes closed.
Cacic's side were playing the prettier stuff but the general quality was a hodgepodge.
The prettier the person, the more money they make – it's a direct correlation.
Sometimes he refracted one of the prettier cello lines, creating canons.
Write better and faster with AI suggestions while staying true to your unique style.
Since I tried Ludwig back in 2017, I have been constantly using it in both editing and translation. Ever since, I suggest it to my translators at ProSciEditing.

Justyna Jupowicz-Kozak
CEO of Professional Science Editing for Scientists @ prosciediting.com