Who is Mi-na's older brother?
He is Min-su.Min-su is.
Who is Mi-na's new friend?
He is Mike.
Mike is.
What is Mi-na's pet?
A dog is.
It is a doge.
She is a dog.
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Are all the answers to the questions all correct? Which ones are commonly used?
Everything looks good except for "A dog is." It's not common in usage at all.
Also be sure to check the spelling of "dog" in the second answer for the pet.
=)