goes very slowly [slow]

[Shandol]

English Vocabulary in Use

This car goes very fast. It is a fast car.

This car goes very slowly. It is a slow car.

Does that mean "slow" is a wrong choice of word?

This car goes very slow. It is a slow car.

 

[Uncle Jack]

The writer is trying to make it clear that "fast" is both an adjective and an adverb, whereas "slow" is only an adjective; the adverb is "slowly".

Does that mean "slow" is a wrong choice of word?

This car goes very slow.

Traditionally, yes. However, "slow" is increasingly used as an adverb, and I am sure you will hear things like "This car goes very slow". I do not recommend you copy this usage though; using "slow" in this way is still generally regarded as an error.

 

[Shandol]

Thank you.

 

[Barque]

I wouldn't say it's still regarded as an error. It's a recognised meaning in most dictionaries. In some contexts I think it fits better than "slowly", such as telling someone to go slow, meaning "Be cautious/careful". (Yes, the OP was asking about the usual, literal meaning but it is used figuratively too.)