Translation:He does not go swimming because he is not well.
well, we would say either "not well," "unwell" or "sick." (or "ill.") We would NOT say "not fine."
I have so much trouble trying to translate these sentences into something that duolingo will accept that I don't know if I am learning anything. Most of it translates into odd sounding English
A lot of times it is not about learning Vietnamese. It is about guessing what answer Duolingo will accept.
"He does not go swimming because he is not fine." Garbage English. Native speakers say "not well."