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 have a picnic with my friends on the park. When it was rain in afternoon, but I haven't umbrella. So I get wet. I felt cold and have a headache. My friends get me to the hospital, the doctor said I was fever. He gave me some medicines andtold me go home to have a good rest.

Corrected essay:
Last Sunday, I had a picnic with my friends in the park. It was rainy in the afternoon, but I didn't have an umbrella. So I got wet. I felt cold and had a headache. My friends took me to the hospital, and the doctor said I had a fever. He gave me some medicine and told me to go home to have a good rest.

Error analysis:
error_sentence: Last Sunday, I have a picnic with my friends on the park.
correct_sentence: Last Sunday, I had a picnic with my friends in the park.
error: have
correction: had
error_type: Verb Tense Error
error_severity: 3
error_description: ① Verb Tense Error: According to English grammar rules, when a sentence contains an adverbial explicitly indicating past time (such as 〈Last Sunday〉), the predicate verb should be in the past tense to describe past events. The original sentence uses 〈have〉 in the present tense, which is inconsistent with the past time indicated by the time adverbial; this is a verb tense error. 〈have〉 needs to be changed to the past tense form 『had』 to comply with grammar rules and context.

error_sentence: Last Sunday, I have a picnic with my friends on the park.
correct_sentence: Last Sunday, I had a picnic with my friends in the park.
error: on
correction: in
error_type: Preposition Error
error_severity: 3
error_description: ① Preposition Error: According to English expression conventions, the fixed prepositional phrase for expressing the location 'inside the park' is 『in the park』. The original sentence uses 〈on the park〉, which does not conform to the idiomatic rules for expressing location in English; this is a preposition error. 〈on〉 needs to be changed to 『in』 to comply with the correct preposition usage standards.

error_sentence: When it was rain in afternoon, but I haven't umbrella.
correct_sentence: It was rainy in the afternoon, but I didn't have an umbrella.
error: When it was rain in
correction: It was rainy in the
error_type: Sentence Structure Error
error_severity: 5
error_description: ① Sentence Structure Error: According to English grammar rules, a clause introduced by 〈When〉 must have a logical relationship with the main clause. In the original sentence, 〈When it was rain in afternoon〉 contradicts the main clause logically and lacks structural coherence; this is a sentence structure error. 〈When〉 should be deleted and changed to the independent sentence 『It was rainy in the afternoon』 to maintain clarity; ② PoS Confusion Error: When describing weather conditions, an adjective is needed as the predicative. The original sentence uses 〈rain〉, a noun, which cannot directly describe the weather; this is a morphology error / PoS confusion. 〈rain〉 should be changed to the adjective 『rainy』; ③ Determiner Error: According to English grammar rules, when expressing 'in the afternoon', the definite article 〈the〉 is required to modify 〈afternoon〉. The original sentence lacks the definite article before 〈afternoon〉; this is a determiner error. The definite article 『the』 needs to be added before 〈afternoon〉.

error_sentence: When it was rain in afternoon, but I haven't umbrella.
correct_sentence: It was rainy in the afternoon, but I didn't have an umbrella.
error: haven't
correction: didn't have an
error_type: Verb Tense Error
error_severity: 4
error_description: ① Verb Tense Error: According to the prompt, the event occurred last Sunday. When describing past events, the simple past tense should be used. The tense of 〈haven't〉 in the original sentence does not match the context; this is a verb tense error. 〈haven't〉 needs to be changed to the past tense form 『didn't have』; ② Auxiliary Error: Based on the sentence tense, this is a negative form of the simple past tense, which requires the structure 'didn't + base form of the verb'. Therefore, the auxiliary verb 『didn't』 needs to be added, followed by the base form of the verb 『have』, changing it to the complete form 『didn't have』; ③ Determiner Error: The countable noun 〈umbrella〉 requires an indefinite article when used generically. The original sentence lacks an indefinite article; this is a determiner error. The indefinite article 『an』 should be added before 〈umbrella〉.

error_sentence: So I get wet.
correct_sentence: So I got wet.
error: get
correction: got
error_type: Verb Tense Error
error_severity: 3
error_description: ① Verb Tense Error: According to English grammar rules, when the action described in a sentence occurred in the past and is related to past events narrated in the context, the predicate verb should be in the past tense. The original sentence uses 〈get〉 in the present tense, which is inconsistent with the temporal logic of the past events in the context; this is a verb tense error. 〈get〉 needs to be changed to the past tense form 『got』 to maintain tense consistency and comply with grammar rules.

error_sentence: I felt cold and have a headache.
correct_sentence: I felt cold and had a headache.
error: have
correction: had
error_type: Verb Tense Error
error_severity: 3
error_description: ① Verb Tense Error: According to English grammar rules, the tenses of coordinate predicate verbs in a sentence must be consistent. In the original sentence, the first predicate verb 〈felt〉 is in the past tense, while the second predicate verb 〈have〉 is in the present tense, resulting in inconsistent tenses; this is a verb tense error. 〈have〉 needs to be changed to the past tense form 『had』 to maintain tense consistency and comply with grammar rules.

error_sentence: My friends get me to the hospital, the doctor said I was fever.
correct_sentence: My friends took me to the hospital, and the doctor said I had a fever.
error: get
correction: took
error_type: Verb Choice Error
error_severity: 3
error_description: ① Verb Choice Error: According to English grammar rules and semantic conventions, forms of 〈take〉 are typically used to express 'taking someone somewhere'. The original sentence uses 〈get〉, meaning 'obtain', which does not fit the context of 'friends took me to the hospital'; this is a verb choice error. 〈get〉 needs to be changed to 『took』 to accurately convey the meaning.

error_sentence: My friends get me to the hospital, the doctor said I was fever.
correct_sentence: My friends took me to the hospital, and the doctor said I had a fever.
correction: and
error_type: Conjunction Error
error_severity: 3
error_description: ① Conjunction Error: According to English grammar rules, two independent clauses must be connected by a conjunction to avoid a comma splice error. The original sentence lacks a suitable conjunction between the two independent clauses 〈My friends took me to the hospital〉 and 〈the doctor said I had a fever〉, making the sentence logically incoherent. The conjunction 『and』 should be added here to connect the two clauses, making the sentence structure complete and logically clear.

error_sentence: My friends get me to the hospital, the doctor said I was fever.
correct_sentence: My friends took me to the hospital, and the doctor said I had a fever.
error: was
correction: had a
error_type: Verb Choice Error
error_severity: 3
error_description: ① Verb Choice Error: According to English expression conventions, the common way to describe 'having (an illness)' is the verb phrase 'have + a + noun for the illness'. The expression 〈was fever〉 in the original sentence does not conform to convention; 'fever' is a countable noun requiring the article 'a' before it, and 'was' cannot be used this way. This is a verb choice error; 'was' should be changed to 'had a' to comply with the standard grammar for expressing illness in English.

error_sentence: He gave me some medicines andtold me go home to have a good rest.
correct_sentence: He gave me some medicine and told me to go home to have a good rest.
error: medicines andtold me
correction: medicine and told me to
error_type: Nonfinite Verb Form Error
error_severity: 4
error_description: ① Noun Number Error: According to English grammar rules, when 〈medicine〉 means 'medication', it is an uncountable noun and cannot be pluralized. The use of 〈medicines〉 in the original sentence is incorrect; this is a noun number error. It needs to be changed to the singular form 『medicine』; ② Space Error: According to English writing conventions, there should be appropriate spaces between words. In the original sentence, 〈andtold〉 is not separated, which does not comply with writing standards; this is a space error. It needs to be separated into 『and told』; ③ Nonfinite Verb Form Error: According to English grammar rules, the correct expression for 'tell someone to do something' is 'tell sb to do sth'. The structure 〈told me go home〉 in the original sentence is incorrect; this is a nonfinite verb form error. 『to』 needs to be added before 〈go〉, changing it to 『told me to go home』.