Don’t confuse “further” and “farther.”
“Further” can be an adverb or an adjective. As an adverb, it means to a greater degree: The disobedient child further annoyed her tired mother. As an adjective, it means additional: Eddie needed further help.
“Farther” can also be an adverb or an adjective. As an adverb, it means to a greater distance: The library is a little farther down this road. As an adjective, it means more distant: There are more coconuts on the farther side of the island.
Remember that in either form, the word “farther” always involves measurable distance. If you could use a ruler on something, “farther” is correct. If not, “further” is the word you’re looking for.
