Writing prompt: Written Expression. Assume you are Lin Chen and have just made a new pen pal named Ted. Please write a letter to him describing your personal background, family situation, and your plan to visit Beijing over the summer. Writing hints: Tian'anmen Square, the Palace Museum, Beijing Roast Duck.
Dear Ted,
________
Welcome to China. Have a good day!
Yours,
Lin Chen

Student essay:
I am Lin Chen. I like playing basketball. And I like traving too. My family have four people, my dad, my mom, my sister and me. In summer, I went to Beijing. First I vistered Tian'anmen Square, It was very big. After I went to the Palace Museum. I vistered many valuable things. I ate Beijing Roast Duck. It was very delicerce.

Corrected essay:
I am Lin Chen. I like playing basketball. And I like traveling too. My family has four people: my dad, my mom, my sister and me. In summer, I went to Beijing. First, I visited Tian'anmen Square. It was very big. After that, I went to the Palace Museum. I saw many valuable things. I ate Beijing Roast Duck. It was very delicious.

Error analysis:
error_sentence: And I like traving too.
correct_sentence: And I like traveling too.
error: traving
correction: traveling
error_type: Spelling Error
error_severity: 2
error_description: Spelling Error: According to English spelling rules, the word 〈traving〉 is misspelled; the correct form is 『traveling』, meaning 'traveling'.
error_sentence: My family have four people, my dad, my mom, my sister and me.
correct_sentence: My family has four people: my dad, my mom, my sister and me.
error: have
correction: has
error_type: Subject-Verb Agreement Error
error_severity: 3
error_description: Subject-Verb Agreement Error: The subject 〈My family〉 is a singular collective noun; the verb should be in the singular form 『has』 instead of the plural form 〈have〉 to adhere to the subject-verb agreement principle.
error_sentence: My family have four people, my dad, my mom, my sister and me.
correct_sentence: My family has four people: my dad, my mom, my sister and me.
error: ,
correction: :
error_type: Punctuation Error
error_severity: 2
error_description: Punctuation Error: According to English expression norms, a colon 『:』 should be used before listing family members, not a comma, to clearly separate the main clause from the specific list.
error_sentence: First I vistered Tian'anmen Square, It was very big.
correct_sentence: First, I visited Tian'anmen Square.
error: I vistered
correction: , I visited
error_type: Punctuation Error
error_severity: 3
error_description: ① Punctuation Error: When the adverb 〈First〉 indicating sequence is at the beginning of a sentence, it should be followed by a comma to separate it from the main clause; adding 『,』 makes the sentence structure clear; ② Spelling Error: According to English spelling rules, 〈vistered〉 is misspelled; the correct spelling is 『visited』, meaning 'visited'.
error_sentence: First I vistered Tian'anmen Square, It was very big.
correct_sentence: First, I visited Tian'anmen Square.
error: ,
correction: .
error_type: Punctuation Error
error_severity: 2
error_description: Punctuation Error: The sentences “I vistered Tian'anmen Square” and “It was very big” each contain independent predicate structures and are two separate sentences; they cannot be joined by a comma and must be separated by a period.
error_sentence: After I went to the Palace Museum.
correct_sentence: After that, I went to the Palace Museum.
correction: that,
error_type: Pronoun Error
error_severity: 3
error_description: Pronoun Error: The preposition 〈after〉 lacks an object; adding the pronoun 『that』 to serve as the object of the preposition 〈after〉 forms the prepositional phrase "after that" functioning as a time adverbial.
error_sentence: I vistered many valuable things.
correct_sentence: I saw many valuable things.
error: vistered
correction: saw
error_type: Verb Choice Error
error_severity: 4
error_description: Verb Choice Error: Based on the context, the verb 〈saw〉 better fits the meaning, describing the act of observation; therefore, 〈vistered〉 should be changed to 『saw』.
error_sentence: It was very delicerce.
correct_sentence: It was very delicious.
error: delicerce
correction: delicious
error_type: Spelling Error
error_severity: 2
error_description: Spelling Error: According to English spelling rules, the word 〈delicerce〉 is misspelled; the correct form is 『delicious』, meaning 'delicious'.