"cái" is a classifier which shows that the thing is an object. Viet uses classifers
The dictionary hint says bánh mì is also cake, but "I eat this cake" was not accepted?
Bánh is cake in general. Mì is wheat. Bánh mì = bread. It cannot be cake. There are other wheat cakes but french introduced bread to Vietnam and it became wildly popular. So it took the default name. If you add another word to it, such as bánh mì dừa, then it could be another kind of wheat cakes.
The audio doesn't play for me on this one either. And on a few others as well.
Cảm ơn Angie. Since my post I have discovered that not all of the sentences have audio. I was screen dumping and emailing the support center all those that did not have audio. I was only getting automated replies. It would have been nice if someone at the support center had advised me that I was wasting my time. Anyway here is an exert from one of the main contributors, ckhadung, to the DL VN course.
We finished reviewing all Vietnamese audio files. I submitted them to Duolingo for final verification and implementation a few days ago. There are a few files needed to be re-recorded but the rest of them are good to go. On the other hand, I must announce that there are only 3000 audio files, about 55% of our course content. "I don't like it but I guess things happen that way".
However, let's not consider this a drawback but look on the bright side: the course is almost here! You can take advantage of this course to combine with other external sources to help with your learning of Vietnamese language.
Cannot I answer "Tôi ăn cái bánh mì dày"? What is the difference between "nay" and "day" (and "do")?