"Cái ghế" WAS NOT AN OPTION in my Duolingo page BUT ONLY..."Chiếc ghế" was. I used"Chiếc ghế" and was graded CORRECT. Confusing that my answer is not the answer on this discussion forum. Help Please. Thank you in Advance. :-)
I use gboard and enabled the english and vietnamese keyboards. Duolingo also automatically switches to the correct language for you when you practice too! Like when you need to type in viet then it switches to viet, and the same with english.