"Cô ấy là đứa trẻ."
Translation:She is the child.
In the grammar explanation there is something a little bit unclear about the particles. It says that if there is no word 'mot' your english sentence should contain the word 'the', if there is 'mot', you should use 'a'. so maybe that should be specified just a little because here it is already different. I said 'She is the child' because of the grammar lessons, but it's wrong here.
That rule does not work in English. It implies that "the" is always required when "a" or "an" is not used. That is simply not true in English. "The" is, for example, not used with mass or uncountable nouns except in very specific statements. In the sentence in question here, "the" makes the sentence refer to a specific child presumably already designated as the topic of conversation. "A child" would be new information but "the child" is known.
Sorry but I don't totally agree with you. I'm also a native Vietnamese and I got it wrong typing "She is A child". To be honest, I don't think "She is THE child" would fit in "Cô ấy là đứa trẻ" without any context. We don't know exactly WHICH child she is, do we? "She is A child" is safe to say in this case: "Cô ấy là (MỘT) đứa trẻ" . "She is THE child" would also fit in if we already know who that child is: "Cô ấy là đứa trẻ (NÀY/ĐÓ/ẤY/KIA...)".
Just don't play games with articles in English as they can change the meaning of a whole sentence or, even more, a whole piece of writing. : )
I agree with you. But in fact, the problem is not the English translations but the Vietnamese phrase. I think the two English phrases: "She is the child" and "She is a child" are not wrong. But I have problem typing "Cô ấy là đứa trẻ". Classifier should not be used that way but as you said, with other demonstrative pronouns (này, kia, ấy, đó...)
Yep. Learners of Vietnamese keep asking about how to translate "a" and "the". In Vietnamese, we just don't have articles. And of course, the English sentences are totally fine but the translations into Vietnamese are a bit ambiguous or even wrong without the context. This problem is hard to explain to foreigners, especially at the very beginning of the course. : (