"I wear trousers."
Translation:Tôi mặc quần.
Đôi,váy and mặc all describe wear (s) explain when are the correct uses and the reason for them..
I don't know if it's a mistake but I see an 's' at the end so I typed Tôi mang những cái quần and its wrong.
Since "trousers" includes an "s" at the end of the word itself as plural form, and you couldn't wear more than one at the same time, so you don't need to use "những/các" here.
In addition, you should use "mặc" instead of "mang" here.
"wear" has three main meanings in Vietnamese: "đội", "mặc" and "mang".
"wear" should be translated as "đội" for wearing something (as a hat,etc...) on your head.
"wear" should be translated as "mặc" for wearing clothes includes a shirt, a skirt, pants (trousers).
"wear" should be translated as "mang" for wearing shoes or socks, glasses *.
"wear" is also translated as "đeo" instead of "mang" for wearing things to adorn oneself such as: jewelry, (sun)glasses, a scarf, rings, etc,....