This is the 359th most frequent Hungarian word.
tartja
"Keeps," "holds," or "maintains."
Here 'tartja' is used to mean 'is holding' someone/something physically.
Ő tartja a könyvet.
He/she is holding the book.
Here 'tartja' is used metaphorically to mean 'keeps' in the context of maintaining a promise.
Mindig tartja az ígéretét.
He/she always keeps his/her promise.
Here 'tartja' is used to express 'conducts/holds' in a professional or scheduled activity context.