how to say "its was able to move very fast"?
is this correct "podía a mover muy rápido". In this instance I am talking about an old car.
6 Answers
Fast and rápido are adjectives.
If you are describing the manner in which it moves you need to use adverbs in correct English and Spanish:
Quickly and rápidamente.
The car is fast. The car goes quickly.
Since writing the above, I've found out that fast is indeed an adverb as well as an adjective. I never knew that and after so many years of 'knowing' its use as an adverb to be wrong, it does sound incorrect to me.
I see that RAE lists rápido as an adverb too - living and learning...
So do you say afowen that you don't use "fast" as an adverb (because the fact is, it is)? You say you aren't a member of those "social groups"? What's with this "regionalism"? I doubt that this form is not used all throughout the English-speaking world.
Deanski, it almost sounds as if you are being defensive. I don't believe that you are not aware that language differs between region and social groups.
A notable difference between British and American Englishes is that it is far more prevalent in the US to use adjectives where according to rules of grammar, adverbs should be use. Of course, when forms of speech become normal, there is often little point in talking about what is 'right' and what is 'wrong'. And if all parties concerned understand what is being said then the communication is effective, many might say 'who cares' if those of a grammatical bent tell them they are wrong.
In this case I am wrong regarding the word fast. I have always used quickly as the adverbial form of fast and where I grew up it was maintained that this was the case and that to use fast adverbially was incorrect, to the extent that it sounds incorrect to me.
That particular example notwithstanding, the case is that in some social groups and I suspect regions within the the UK (though I can't be bothered to think about it), using adjectives as adverbs is part of normal speech and I have noted that this is more so the case with American English speakers.
Un abrazo, Alex
Fast and rápido are adjectives.
If you are describing the manner in which it moves you need to use adverbs in correct English and Spanish:
Quickly and rápidamente.
The car is fast. The car goes quickly.
Fast & rápido, while being adjectives, are also used as adverbs.
The car moves fast. = El coche anda rápido.
Era capaz de moverse muy rápido
Fue capacido moverse rapidamente.
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If we are talking about a sprey or a shaker we use: agitar
If one people is moving we can use: andar, caminar, correr.
Podía mover muy rápido. 
What about: Era capaz de moverse/ir/viajar muy rápido?
