"I wear a sweater and a scarf."
Translation:Tôi mặc áo lạnh và khăn quàng.
Notice previous question "Tôi muốn một đôi tất, một đôi ủng và một cái khăn quàng. "Một used for each item, including "scarf" which is implied just one scarf. Don't understand how the rule above with "empasize the number of sweaters or scarfs in this instance. Please assist. I Thank you in Advance for your kind help :-)
I think that, since in the sentence you provided the speaker is listing things that they want, the quantity isn't at all implied. One could very possibly desire more that one scarf in fact. In this sentence however the speaker is talking about things that they wear habitually hence the quantifier can be safely omitted. I am not a native speaker though, so this is just my interpretation.
I think if you're wearing it you're not counting it, so no một. If you are buying it off the shelf then you are counting it as one sweater. But the Vietnamese assume, in the way they think, they wear sweater. Idiomatic language characteristic of Vietnamese. This is not English, after all
Often might be a bit strong... I've checked quite a few with a professor I know, and I've found the difference is mostly dialectical rather than incorrect. Still, anything translated can be screwed up to h*ll and back because it is just impossible to get a perfect translation between two languages as different as Vietnamese and English.