Writing prompt: My Favorite Teacher

Student essay:
My favourite teacher
Dear Henry,I'm glad to hear from you.I got to know that your favourite teacher is Mr.Green.I'd like to tell you something about my favourite teacher.
She is my chemistry teacher.During my first month at High School,I met many new teachers and students.But the teacher I like best is my chemistry teacher.She is not only strict,but also warm-hearted.I failed in the first exam.She encouraged me a lot,and helped me with my study as well.What's more,I love her teaching methods very much.Because of her help,I make great progress now.I think she is one of the most fantastic teacher I have ever met.I felt warm and aggressive with her.During the three years we will struggle together,we will get on well with each other.I love her so much.
Yours,Li Hua

Corrected essay:
My favourite teacher
Dear Henry,
I'm glad to hear from you. I got to know that your favourite teacher is Mr. Green. I'd like to tell you something about my favourite teacher.
She is my chemistry teacher. During my first month at High School, I met many new teachers and students. But the teacher I like best is my chemistry teacher. She is not only strict, but also warm-hearted. I failed in the first exam. She encouraged me a lot, and helped me with my study as well. What's more, I love her teaching methods very much. Because of her help, I make great progress now. I think she is one of the most fantastic teachers I have ever met. I feel warm and motivated with her. During the three years we will struggle together, we will get on well with each other. I love her so much.
Yours,
Li Hua

Error analysis:
error_sentence: My favourite teacher
Dear Henry,I'm glad to hear from you.
correct_sentence: My favourite teacher
Dear Henry,
I'm glad to hear from you.
error: I'm
correction: 
I'm
error_type: Format Error
error_severity: 5
error_description: Format Error: According to English writing conventions, the salutation 〈Dear Henry〉 in an English letter format requires a line break to separate it from the body text; therefore, a line break is added afterwards to conform to standard letter format conventions.

error_sentence: I'd
correct_sentence: I'd like to tell you something about my favourite teacher.

error: I'd
correction: I'd
error_type: Other Error
error_description: Other Error: Unreasonable segmentation.

error_sentence: I think she is one of the most fantastic teacher I have ever met.
correct_sentence: I think she is one of the most fantastic teachers I have ever met.
error: teacher
correction: teachers
error_type: Noun Number Error
error_severity: 2
error_description: Noun Number Error: According to English grammar rules, 〈one of〉 should be followed by a plural noun to mean 'one of...', in the original sentence, 〈teacher〉 should be in the plural form; therefore, 〈teacher〉 should be changed to 『teachers』 to comply with English grammar rules.

error_sentence: I felt warm and aggressive with her.
correct_sentence: I feel warm and motivated with her.
error: felt
correction: feel
error_type: Verb Tense Error
error_severity: 3
error_description: Verb Tense Error: According to the context, this action should use the simple present tense, while in the original sentence 〈felt〉 is in the simple past tense; therefore, 〈felt〉 needs to be changed to 『feel』 to fit the context.

error_sentence: I felt warm and aggressive with her.
correct_sentence: I feel warm and motivated with her.
error: aggressive
correction: motivated
error_type: Adjective Error
error_severity: 2
error_description: Adjective Error: According to the context, the intended meaning here is 'motivated'; 〈aggressive〉 means 'invasive' and does not align with the positive emotion expressed in the context; therefore, 〈aggressive〉 needs to be changed to 『motivated』 to fit the semantics.

error_sentence: Yours,Li Hua
correct_sentence: Yours,
Li Hua
correction: 

error_type: Format Error
error_severity: 5
error_description: Format Error: According to English writing conventions, a line break is required between the closing 〈Yours〉 and the signature 〈Li Hua〉 at the end of a letter; therefore, a line break is added to conform to standard English letter format standards.