1.I have a play mate
correct: I have a playmate.
Explanation. Don't forget your period(.)
> playmate is one word.
2.It is not good to compete in the school.
CORRECT
3.I am too bored when I learn samething everyday.
correct: I am too bored when I learn same thing everyday.
4.I am sharing my pencil.
CORRECT
5.We have to be nice.
CORRECT
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Hello my handsome Tony!!
I was so happy to read your message. I could imagine you say the phrase "GO DOWN!" Anyway, I am also happy because you are one of my students. Always keep that charm on you. Stay sweet and be responsible always. I know your a nice guy. Don't forget to check my corrections.