You know the phrase that's usually said in a sing-song manner? Which is the correct one?
I only ever hear it in spoken form, so I'm not sure if I'm mishearing it.
Also, is there a comma in this phrase? Like "No, can do" or "No, can't do"
This is a literal English translation of the Chinese 不可以 (不 = No, 可以 = Can/Yes) which means "Cannot". When 不可以 is translated directly to English it ends up as "No can do" which was originally used by Chinese immigrants to Western countries in their attempt to speak English by directly translating words from their own language into English.
"No can do" means "I can not do that", and there is an implication "It might be possible, but I'm not willing to try." It does not have a comma. I think the phrasing is meant to imply simplified English, as if speaking to a non-native speaker.
"No, can't do" is not in common usage.
The phrase was originally a way to mock Chinese people, according to Oxford Dictionaries.
The widespread use of the phrase in English today has obscured its origin: what might seem like folksy, abbreviated version of I can’t do it is actually an imitation of Chinese Pidgin English. The phrase dates from the mid-19th to early-20th centuries, an era when Western attitudes towards the Chinese were markedly racist.
—Adeshina Emmanuel, Common Words and Phrases That Have Seriously Racist Roots (April 10, 2016)
No(-) can(+) do implies someone is not able to do something.
No(-) can(+)not(-) do implies that whatever he or she is doing is impossible not to do.
There is no comma in this phrase.