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 park. In the afternoon, the key was rain. But I forgot take my umbrella, so I was wet. I felt cold and I had a headache. My friends were take me to the hospital. The doctor asked I have a fever and gave me some medicine.

Corrected essay:
Last Sunday, I had a picnic with my friends in the park. In the afternoon, the weather was rainy. But I forgot to take my umbrella, so I was wet. I felt cold and I had a headache. My friends took me to the hospital. The doctor said I had a fever and gave me some medicine.

Error analysis:
error_sentence: In the afternoon, the key was rain.
correct_sentence: In the afternoon, the weather was rainy.
error: key was rain
correction: weather was rainy
error_type: PoS Confusion Error
error_severity: 4
error_description: ① Noun Error: According to the context, the sentence describes the weather; the noun 〈key〉 used as the subject to express weather change should be replaced with the English word for "天气", 『weather』, to fit the context; ② PoS Confusion Error: According to English grammar rules, the linking verb 〈was〉 should be followed by an adjective to form a predicative structure describing the weather condition. Therefore, the noun 〈rain〉 needs to be changed to the adjective 『rainy』 to form a complete predicative structure consistent with the original meaning and grammatical rules.
error_sentence: But I forgot take my umbrella, so I was wet.
correct_sentence: But I forgot to take my umbrella, so I was wet.
correction: to
error_type: Nonfinite Verb Form Error
error_severity: 3
error_description: Nonfinite Verb Form Error: According to English grammar rules, "forget to do something" is a fixed phrase; the verb 〈forgot〉 should be followed by an infinitive structure to indicate doing something. Therefore, there is a nonfinite verb form error here. The base form 〈take〉 needs to be changed to 『to take』 to comply with English grammar rules and the original meaning.
error_sentence: My friends were take me to the hospital.
correct_sentence: My friends took me to the hospital.
error: were take
correction: took
error_type: Verb Tense Error
error_severity: 4
error_description: ① Verb Voice Error: According to the original meaning, the sentence expresses "friends took me to the hospital"; the relationship between the subject "friends" and the verb "took" is active. The simple past active voice should be used. Therefore, the auxiliary verb 〈were〉 for the simple past passive voice needs to be deleted to match the original meaning; ② Verb Tense Error: According to the original meaning, the sentence expresses "friends took me to the hospital"; the action occurred "Last Sunday", so the verb needs to be in the simple past tense. 〈take〉 needs to be changed to its simple past form 『took』 to match the context's tense.
error_sentence: The doctor asked I have a fever and gave me some medicine.
correct_sentence: The doctor said I had a fever and gave me some medicine.
error: asked I have
correction: said I had
error_type: Verb Choice Error
error_severity: 4
error_description: ① Verb Choice Error: According to the prompt, the intention is to express "the doctor said I had a fever", which is stating an objective fact without the meaning of "command" or "request". The action of "saying; stating" should be emphasized. Therefore, the verb 〈asked〉, which implies "command" or "request", needs to be changed to 『said』, meaning "talk; say; state", to align with the original prompt; ② Verb Tense Error: 〈I have a fever〉 is the content of the object clause following the verb 〈said〉. According to the context, the action occurred "Last Sunday", so the verb needs to be in the simple past tense. Therefore, the base form 〈have〉 needs to be changed to 『had』 to match the context's tense.