"L'enfant est-il chinois ?"
Translation:Is the child Chinese?
No. There are three ways of structuring a question (with a "yes/no" answer) in French. In speech, one can form a question by simply saying a phrase with the inflection of a question. This form isn't generally used in writing.
Ex. "L'enfant est chinois ?"
The second way, which is commonly used both in speech and in writing uses "est-ce que" which literally means "is it that" but is usually translated into English with the verbs "to be" or "to do."
Ex. "Est-ce que l'enfant est chinois ?"
The third way, which we see here, is the most formal, and is the most likely form to be seen in novels and other published work. To form this type of question, one inverts the pronoun and the verb and hyphenates them. A pronoun must always be used with inversion, so if the subject is named (i.e. not using a pronoun), a pronoun must be added to the sentence to create the question.
Ex. "L'enfant est-il chinois ?"
With pronoun only:
"Est-il chinois ?"
EDIT: To the above three, I should add a fourth way, which is perhaps the most natural in informal settings. In this case, the first part of the question is structured like a statement, followed by the subject of the sentence (and your voice should go up in pitch on the last word):
Ex. "Il est chinois, l'enfant ?"
Which you'd likely hear pronounced: "Y est chinois, l'enfant ?"
But I would recommend sticking with the second or maybe the first way until your French is more advanced.
And in Québec, there's a fifth way which is slightly different from the fourth, but I won't get into that unless someone asks!
That's the tricky thing with French. If you say, "Cette personne là, elle est incroyable," you could, theoretically, be referring to a man. I seem to remember something about an exception with "enfant," but I'm uncertain. If I'm wrong, then it means that "il" here is just referring back to the gender of the word "enfant" and doesn't actually have to do with the actual gender of the child.
Not as you've written them, no, because there's a verb missing, among other things.
"Est-ce que" does, obviously, have a verb in it, but the clause following it also needs to have a verb in it.
So to use "est-ce que," you'd need to say, Est-ce que l'enfant est chinois? (You don't need the subject pronoun, because there's no inversion.)
If you really want to use a repeated subject, you can say L'enfant, est-ce qu'il est chinois?, but there's very little reason to.