Writing prompt: My Favorite Teacher

Student essay:
Dear Henry,
I am glad to hear that you get on very well with your maths teacher,Mr Green.Now I'd like to tell you about my favourite teacher.His name is Yang Zhe.Mr Yang is a physics teacher.I like his teaching methods.When he talks to others,he always has a smile on his face. He is not only quite friendly,nut also humorous.In his class,you will never feel bored.He always gives us some advices about how to learn physics well.
One day,I failed an exam.After that,he helped me improve my physics and we dealed with difficult problems together.Finally,I got very good grades.
He helped me a lot.I will never forget him.He is my favourite teacher.

Corrected essay:
Dear Henry,
I am glad to hear that you get on very well with your maths teacher, Mr. Green. Now I'd like to tell you about my favourite teacher. His name is Yang Zhe. Mr. Yang is a physics teacher. I like his teaching methods. When he talks to others, he always has a smile on his face. He is not only quite friendly, but also humorous. In his class, you will never feel bored. He always gives us some advice about how to learn physics well.
One day, I failed an exam. After that, he helped me improve my physics and we dealt with difficult problems together. Finally, I got very good grades.
He helped me a lot. I will never forget him. He is my favourite teacher.