This is the 320th most frequent Afrikaans word.
vf
"Vf" is not an Afrikaans word. It may be a typo or abbreviation.
In this sentence, 'vf' is used as a shorthand to mean 'vreeslike', colloquial for 'terribly' or, more naturally in English, 'incredibly'.
Sy is 'n vf ('vreeslike') goeie student.
She is an incredibly good student.
Here, 'vf' is an abbreviation or shorthand form often used colloquially or in messages for 'versigtig', meaning careful.
Ek het 'n boek wat ek vf ('versigtig') gaan hanteer.
I have a book that I will handle carefully.
Here, 'vf' stands for 'veilig', which means safe.