posted by rfvv .
1. First, let me introduce my friend to you. His name is Seho. He is my classmate. He is also my neighbor. He got the first prize in the English speech contest.
2. First, I'd like to introduce my classmate, who is my neighbor and got the first prize in the writing contest.
3. My neighbor has a son who is my classmate. I met him for the first time at Yunsan Middle School. He got the first prise in the dance contest.
(Are the sentences grammatically correct? Would you check them?)
Yes, they are all grammatically correct.
Note in 3 -- prize