建议改成:
I went to the playground and played basketball this morning.I went there early.I was the only one in the playground.Later,a boy came.first,I saw he was not tall.I thought he still study in a primary school.But at last,I felt he was headsome.I thought he was a grace boy.He sometimes picked up the ball for me.I was a little interested in him.
还有,你的文章有矛盾,太中文化了。