Writing prompt: Using the given vocabulary and sentence patterns, and referring to the picture, write a short essay. It is 3 PM. Based on the information provided below about Linda, use the present continuous tense to describe what Linda sees and hears at the mall:
Writing hints:
A little girl: buy some food
A young lady: look at a dress
Linda's mother: try on the shoes
Linda's father: stay on the sofa; wait for

Student essay:
At 3:00 p.m,Lina is in a shopping mall. A little girl is buying some food. A young lady is looking at a dress. Linda's mother is trying a pair of shoes. Linda'a father is staying on the sofa ad waiting for Linda's mother.

Corrected essay:
At 3:00 p.m., Linda is in a shopping mall. A little girl is buying some food. A young lady is looking at a dress. Linda's mother is trying on a pair of shoes. Linda's father is staying on the sofa and waiting for Linda's mother.

Error analysis:
error_sentence: At 3:00 p.m,Lina is in a shopping mall.
correct_sentence: At 3:00 p.m., Linda is in a shopping mall.
error: p.m,Lina
correction: p.m., Linda
error_type: Punctuation Error
error_severity: 5
error_description: ① Punctuation Error: According to English writing conventions, the time abbreviation 〈p.m〉 requires periods to indicate abbreviation, so 〈p.m〉 is corrected to the standard form 『p.m.』; ② Space Error: According to English writing conventions, a space should follow the comma 〈,〉 when connecting clauses, so 〈p.m,Lina〉 is modified to 『p.m., Lina』; ③ Spelling Error: According to the prompt requirements, 〈Lina〉 is misspelled and should be corrected to the proper name form 『Linda』 to match the context.

error_sentence: Linda's mother is trying a pair of shoes.
correct_sentence: Linda's mother is trying on a pair of shoes.
correction: on
error_type: Preposition Error
error_severity: 3
error_description: Preposition Error: According to English fixed phrases, the verb 〈trying〉 needs to be paired with the preposition 『on』 when expressing “trying on clothes” to clarify the object of the action, therefore it is modified to the phrasal verb 『trying on』 to fully express the meaning of “trying on shoes”.

error_sentence: Linda'a father is staying on the sofa ad waiting for Linda's mother.
correct_sentence: Linda's father is staying on the sofa and waiting for Linda's mother.
error: Linda'a
correction: Linda's
error_type: Spelling Error
error_severity: 3
error_description: Spelling Error: According to English grammar rules, the possessive form of a singular noun should add 『's』 at the end, but the original word 〈Linda'a〉 is misspelled, so it is corrected to the proper possessive form 『Linda's』 to accurately express possession.

error_sentence: Linda'a father is staying on the sofa ad waiting for Linda's mother.
correct_sentence: Linda's father is staying on the sofa and waiting for Linda's mother.
error: ad
correction: and
error_type: Spelling Error
error_severity: 2
error_description: Spelling Error: According to standard English vocabulary, the conjunction 〈ad〉 used to indicate coordination is a spelling error; it should be corrected to the standard spelling 『and』 to correctly connect the present participles 〈staying〉 and 〈waiting〉, making the sentence structure logically consistent with parallel actions.