Hello, James! It's nice to see your homework composition about yourself. Please study about the corrections...

    ***********CORRECTED ESSAY OF JAMES CHOI************

My name is James. And my korean name is ?????????
I am 12 years old. My hobby is making gundam.
My favorite subject is math because it has always an answer.

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James: My favorite subject is math.
Because always math has answers.
Correct: My favorite subject is math because it has always an answer.

>> Conjunctions like BECAUSE, BUT, SO, etc. are used to connect 2 clauses. Therefore, we should not separate the clauses.

>> Avoid repeating the same  noun twice. You may use pronouns instead (movie ---> it).

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That's it, James! Please study about the explanations above. You sis a great job in introducing yourself to me. So, math is your favorite subject! That's really amazing. Actually, that is the weakness of most of the students so you are really fantastic!

~Teacher Ace