Quick vs. quickly

Q:

What is the difference in usage between quick and quickly as adverbs, as in these examples:

(a)	Come back quick.
(b)	She checked to see that nothing was coming and walked quickly across the road.

Osvaldo Musto
mustobarello@arnet.com.ar

A:

Quickly is the adverb form of quick. Many dictionaries, however, describe quick as a very informal use of quickly, as in your first example, sentence (a).

You might hear:

However, these sentences above—sentences (c) and (d)—are considered by many to be too colloquial.

In most speech, and certainly in writing, quickly is used as the adverb.

(e)	The police came quickly.
(f)	The fire fighters quickly put out the fire.
(g)	We need to finish this project as quickly as possible.