Incorrect spelling, explanation: this form is a mistake because nothing in the etymology indicates that the word prefer should be spelled with a double consonant. Looking back then, we can find out it was always written with one -f. Therefore, preffer is an incorrect form and the correct one is: prefer.

Correct spelling, explanation: prefer is a verb, which originates from Old French preferer (14c.), Latin praeferre and late 14c. preferren. As we can see, all the previous forms were spelled with one -f. That’s why there’s no need to add the second consonant – preffer does not exist in a dictionary.

Definition of prefer:
verb, like, choose, want one thing rather than another
What do you prefer – still water or sparkling water?
I prefer not to go to the gym.

Collocations with prefer:
Some most commonly used collocations include: prefer sth/sb to sth/sb, prefer sth/sb over sth/sb, and prefer sth/sb or sth/sb.
My mother prefers my brother to me.
I prefer green over black.
Susan doesn’t know if she prefers books or films.

Incorrect spelling

Incorrect spelling