Writing prompt: Based on the given hints and referring to the picture, write a short essay.
Last Sunday, I went for a picnic in the park with my friends. It started raining in the afternoon. I forgot my umbrella and got wet. I felt cold and had a headache. My friends took me to the hospital. The doctor said I had a fever. He gave me some medicine and told me to go home and rest well.
Writing hints: picnic; rain; umbrella; get wet; hospital; fever; medicine.

Student essay:
last weekend, I and my friends go to a park for a picnic. Afternoo is rain, I don't have an umbrella, I get wet.

Corrected essay:
Last weekend, my friends and I went to a park for a picnic. In the afternoon, it was rainy, but I didn't have an umbrella. I got wet.

Error analysis:
error_sentence: last weekend, I and my friends go to a park for a picnic.
correct_sentence: Last weekend, my friends and I went to a park for a picnic.
error: last
correction: Last
error_type: Case Error
error_severity: 2
error_description: Case Error: The first letter of the first word in an English sentence should be capitalized; therefore, 〈last〉 is changed to 『Last』 to conform to English writing conventions.

error_sentence: last weekend, I and my friends go to a park for a picnic.
correct_sentence: Last weekend, my friends and I went to a park for a picnic.
error: I and my friends go
correction: my friends and I went
error_type: Word Order Error
error_severity: 5
error_description: ① Word Order Error: In English, the order of multiple pronouns should be 〈third person + first person〉; therefore, 〈I and my friends〉 is changed to 『my friends and I』; ② Verb Tense Error: In English, past events should be described using the past tense; therefore, 〈go〉 is changed to 『went』.

error_sentence: Afternoo is rain, I don't have an umbrella, I get wet.
correct_sentence: In the afternoon, it was rainy, but I didn't have an umbrella.
error: Afternoo is rain, I do
correction: In the afternoon, it was rainy, but I did
error_type: Sentence Structure Error
error_severity: 5
error_description: ① Spelling Error: According to English writing conventions, 〈Afternoo〉 should be spelled as 『afternoon』, meaning 'afternoon'; ② Preposition Error: 'In the afternoon' typically uses the preposition 『In』 to form a time adverbial; ③ Determiner Error: Nouns require determiners for modification; here, 『afternoon』 needs the definite article 'the' to specify that particular afternoon; ④ Sentence Structure Error: Describing weather conditions should use 'it' as the subject combined with the past tense; therefore, it is changed to 『it was rainy』 to form a complete sentence; ⑤ Conjunction Error: Based on the context, the conjunction 『but』 needs to be added to indicate a contrast; ⑥ Verb Tense Error: The original text is in the simple past tense, so 'don't' needs to be changed to 'didn't'.

error_sentence: Afternoo is rain, I don't have an umbrella, I get wet.
correct_sentence: In the afternoon, it was rainy, but I didn't have an umbrella. I got wet.
error: , I get
correction: . I got
error_type: Verb Tense Error
error_severity: 4
error_description: ① Punctuation Error: In English, two independent clauses '...but I didn't have an umbrella' and 'I got wet' cannot be directly connected by a comma 〈,〉; it needs to be changed to a period 『.』 for separation; ② Verb Tense Error: According to the context, the entire text should use the simple past tense, so the verb 〈get〉 is changed to the past tense 『got』 to maintain tense consistency.