"He counts fast" is improper English, isn't it? You don't verb adjective, you verb adverb.
Is this how portuguese is actually spoken-- using rápido instead of rapidamente? or is this just because duolingo hasn't taught us adverbs yet?
Quickly is an adverb meaning rapidamente. In Portuguese it would sound weird, but it's ok in English.
2013-03-13 It's not jut OK in English–it's correct. We're modifying the verb, telling how he counts, so we must use an adverb, "quickly". "Fast" is just wrong, even if it is used frequently colloquially.
I think "He counts quickly" should be acceptable in this instance. You can always give feedback to duolingo whenever you consider you've been marked incorrectly.
It is a better answer! Fast is an adjective and is incorrect. An adverb such as quickly or rapidly is correct.
Tell is also given as a translation for contar. How often is contar used in Brazil to mean tell vs. count? Are falar, dizer and explicar more common to use for tell, speak, say, etc. than contar?
"contar" is most of time related to "jokes", "secrets" and "stories",that is, to spell out/report something. count is always "contar" (count with/on me = conte comigo). sometimes we use contar interchangeably with "dizer". I'll tell you something = vou te falar/dizer/contar uma coisa. So, there's no rule on the usage of "contar" or when it will come up on a conversation.