Shouldn't "We drink rapidly" also be correct?
Does Portuguese use different forms for adjectives and adverbs (like Spanish rápido/rapidamente)?
Yes, the same way! =)
Rápido is used as an adjective or an adverb, right? Then, how do I choose between rápido and rápidamente if I need an adverb?
Rápido is much more common... I don't remember the last time I heard rapidamente! =) but, if you tell a story, for instance, you are more likely to use rapidamente! =)
Thank you so much! Muito obrigado!
Is we are drinking also an acceptable translation?
No, because the statement should be "Nós estamos bebendo".
Then why does it allow me to translate other present tense verbs as either progressive and present and not this one? What is the difference?
Rapido is a adjective, so it reffer to "We". Rapidamente is a adverb, so it reffer to "Drink"
Language is flexible, and "rápido" can be taken as an adverb.
"We drink swiftly" is wrong?
Unusual but not wrong, I'd say
So, rápido, as an adverb, has no plural ending (compared to adjective, e.g. Nós somos rápidos)?
Why is " We quickly drink " wrong?
It a less-common construction in English (unless it's followed by something like "...the wine"), but it should be acceptable. I'd report it.