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 Sunday, I had a picnic with my friends. In the afternoon, it start rain but I didn't take the umberlla. So I got wet, I felt a little cold and I had a headache. My friends took me to the hospital. The doctor said "You are have a fever. You sould eat some medicine and have a rest. "

Corrected essay:
Last Sunday, I had a picnic with my friends. In the afternoon, it started to rain but I didn't take an umbrella. So I got wet. I felt a little cold and I had a headache. My friends took me to the hospital. The doctor said "You have a fever. You should take some medicine and have a rest."

Error analysis:
error_sentence: In the afternoon, it start rain
correct_sentence: In the afternoon, it started to rain but I didn't take an umbrella.
error: start
correction: started to
error_type: Verb Tense Error
error_severity: 3
error_description: ① Verb Tense Error: Based on the time adverbial 〈In the afternoon〉 indicating the action occurred in the past, the base form verb 〈start〉 needs to be changed to the past tense form 『started』 to maintain tense consistency; ② Nonfinite Verb Form Error: According to English verb collocation rules, 〈rain〉 following the verb 〈start〉 should use an infinitive structure; the infinitive marker 『to』 needs to be added to form the complete verb phrase 『started to rain』 to comply with nonfinite verb usage norms.
error_sentence: but I didn't take the umberlla.
correct_sentence: In the afternoon, it started to rain but I didn't take an umbrella.
error: the umberlla
correction: an umbrella
error_type: Determiner Error
error_severity: 2
error_description: ① Determiner Error: Based on the sentence meaning expressing a general concept, the definite article 〈the〉 needs to be changed to the indefinite article 『an』, forming 『an umbrella』 to indicate the general meaning of 'an umbrella'; ② Spelling Error: According to English spelling rules, 〈umberlla〉 is not the correct spelling; it should be changed to the correct spelling 『umbrella』 to express the meaning 'umbrella' and comply with word formation norms.
error_sentence: So I got wet, I felt a little cold and I had a headache.
correct_sentence: So I got wet.
error: ,
correction: .
error_type: Punctuation Error
error_severity: 2
error_description: Punctuation Error: According to English grammar rules, a comma 〈,〉 cannot connect two independent clauses alone. A period 『.』 should be used here to divide the sentence into two independent and complete main clauses 〈So I got wet.〉, conforming to English punctuation usage norms.
error_sentence: The doctor said "You are have a fever.
correct_sentence: The doctor said "You have a fever.
error: are
error_type: Auxiliary Error
error_severity: 3
error_description: Auxiliary Error: According to English grammar rules, 〈have a fever〉 as a complete predicate verb phrase already includes the main verb 〈have〉, and does not require the addition of the auxiliary verb 〈are〉. Therefore, the redundant auxiliary verb 〈are〉 needs to be deleted to make the sentence conform to the grammatical structure norms of a simple declarative sentence.
error_sentence: You sould eat some medicine and have a rest. "
correct_sentence: You should take some medicine and have a rest."
error: sould eat
correction: should take
error_type: Verb Choice Error
error_severity: 3
error_description: ① Spelling Error: According to English spelling rules, the modal verb 〈sould〉 is incorrectly spelled; it should be corrected to the proper spelling 『should』 to conform to the standard writing of modal verbs; ② Verb Choice Error: According to English fixed expressions, the verb used to express 'taking medicine' should be 〈take〉, not 〈eat〉; therefore, 〈eat medicine〉 needs to be changed to the correct collocation 『take medicine』 to comply with idiomatic English usage.