Is “fastly” the adverb of “fast”?

Is “fastly” the adverb of “fast”?

written by Lilian Ndongmo. ESL Teacher

Question: To form an adverb from an adjective, the rule says to add –ly at the end of the adjective. If I add –ly after the word ‘fast’, is fastly correct?

Answer: NO. Fastly is not the adverb of fast. In fact, there is no word like fastly in English. A long time ago, fastly was used as an adverb, but not anymore , so please remove it from your vocabulary.

 The adverb of fast is fast

Examples: Tommy is fast. He finished his exam in less than 30 minutes. (fast = adjective)

Usain Bolt runs very fast. (fast = adverb)

More meanings of fast used as an adverb

1. The baby is fast asleep. (soundly; deeply)

2.  The door was shut fast. (tightly; firmly)

3.  Your clock is running fast. (in advance of the correct time)

4. The river flows fast. (quickly; rapidly; swiftly)