What do the following number words have in common?

Half

Four

Nine

 

HINT:

"Four" and "Nine" have to be changed in certain way.

 

Answer:

 

Each word can be preceded by BE to form a new word, but "Four" must be changed to its homophone "fore", and "Nine" must be changed to its phonetic homophone "nign".

 

BEHALF

BEFORE

BENIGN