There is no need for "fastly" because "fast" is both an adjective and an adverb. So, "I ran fast" is completely correct. The existence of "fast" as an adverb does not preclude the future development of a word "fastly", but it does hinder it.

Aug 29, 2021 · The difference between fast and quick in English is that the former is an adjective, while the latter is a mere adverb. As such, the adjective is a double duty. However, it doesn’t need the -ly suffix.

The word “quickly”, used as an adverb, is synonymous with “fast”, but usually refers to the time an action takes rather than to the speed of movement. For example, you can say Come here, quickly!

As adverbs the difference between fast and fastly is that fast is in a firm or secure manner, securely; in such a way as not to be moved while fastly is securely. As an adjective fast is firmly or securely fixed in place; stable. As a noun fast is a train that calls at only some stations it passes between its origin and destination, typically ...

Fast is a flat adverb, meaning it works adverbially without the -ly ending. Fastly is superfluous.

Fast and quickly are adverbs. We usually use quick to refer to something happening in a short time, or a shorter than expected time: We stopped for a quick snack.

Is it correct to say ‘fast’ or ‘fastly’? What is the meaning of ‘fastly’? Don’t make this mistake anymore. Watch this video to learn the right answer now!

The correct answer is A: fast. But a surprising number of challenge-takers said C. A number of them suggested that quickly would be correct or preferred to either fast or fastly. There were even a handful who wrote “I would probably say A, but I bet B is the right answer.”

Jul 4, 2011 · As well as being an adjective, fast is an adverb. We use it all the time as such: He ran fast. However, though slow is definitely an adjective, it sounds wrong when used as an adverb, because slowly is more common. He ran slow. We would always say: He ran slowly.

Mar 17, 2013 · 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.