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:
At last Sunday , I with my friends went to picnic. But after lunch, the weather chang the rain, I don't have umbrella, I was feel cool and headache. My friends let me went to hospital, doctor saied me fever. He gave me medicine and let me back home have a good free time.

Corrected essay:
Last Sunday, I went with my friends to a picnic. But after lunch, the weather changed to rain. I didn't have an umbrella, so 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 medicine and let me go back home and have a good rest.

Error analysis:
error_sentence: At last Sunday , I with my friends went to picnic.
correct_sentence: Last Sunday, I went with my friends to a picnic.
error: At last
correction: Last
error_type: Word Redundancy Error
error_severity: 4
error_description: Word Redundancy Error: The time adverbial 〈last Sunday〉 means 'last Sunday' and does not require a preceding preposition; therefore, 'At' is deleted.

error_sentence: At last Sunday , I with my friends went to picnic.
correct_sentence: Last Sunday, I went with my friends to a picnic.
correction: went
error_type: Word Order Error
error_severity: 4
error_description: Word Order Error: According to English expression conventions, the sentence structure 〈I with my friends went〉 has a word order error. In English, the subject should be directly followed by the predicate verb; therefore, 『went』 is moved after the subject to form the correct word order 『I went with my friends』.

error_sentence: At last Sunday , I with my friends went to picnic.
correct_sentence: Last Sunday, I went with my friends to a picnic.
error: went to
correction: to a
error_type: Determiner Error
error_severity: 3
error_description: Determiner Error: According to English expression conventions, the noun 〈picnic〉 in 〈went to picnic〉 lacks the necessary article. A singular countable noun requires 『a』 before it to form the fixed phrase 'go to a picnic', meaning 'go for a picnic'; therefore, it is corrected to 'to a picnic'.

error_sentence: But after lunch, the weather chang the rain, I don't have umbrella, I was feel cool and headache.
correct_sentence: But after lunch, the weather changed to rain. I didn't have an umbrella, so I felt cold and had a headache.
error: chang the rain, I do
correction: changed to rain. I did
error_type: Verb Tense Error
error_severity: 4
error_description: ① Verb Tense Error: According to the context describing events from last Sunday, the simple past tense should be used throughout. The author intends to express 'the weather changed and it started to rain', so the verb 'change' should be in the past tense; thus, 〈chang〉 should be changed to the past tense 『changed』; ② Preposition Error: To express the change from good weather to rain, the structure 『changed to rain』 should be used, not 'chang the rain'; ③ Punctuation Error: The clauses 'the weather changed to rain' and 'I didn't have an umbrella' each contain independent predicate structures and are separate sentences; they cannot be joined by a comma and require a period for separation; ④ Auxiliary Error: According to the context describing events from last Sunday, the simple past tense should be used. 〈do〉 needs to be changed to the past tense 『did』 to match the simple past tense.

error_sentence: But after lunch, the weather chang the rain, I don't have umbrella, I was feel cool and headache.
correct_sentence: I didn't have an umbrella, so I felt cold and had a headache.
correction: an
error_type: Determiner Error
error_severity: 3
error_description: Determiner Error: According to English grammar rules, 'umbrella' 〈umbrella〉, as a singular countable noun, requires an indefinite article before it. Due to the initial vowel sound, the indefinite article 『an』 should be used; therefore, 『an』 is added before 〈umbrella〉.

error_sentence: But after lunch, the weather chang the rain, I don't have umbrella, I was feel cool and headache.
correct_sentence: I didn't have an umbrella, so I felt cold and had a headache.
error: I was feel cool and
correction: so I felt cold and had a
error_type: Verb Choice Error
error_severity: 5
error_description: ① Conjunction Error: 'I don't have umbrella' and 'I was feel cool and headache' are two clauses with independent predicate structures lacking a conjunction; therefore, 『so』 is needed to connect the cause-and-effect relationship and enhance sentence coherence; ② Verb Tense Error: According to the context describing events from last Sunday, the simple past tense should be used, and 'to feel something' should be in the active voice; thus, 〈was feel〉 needs to be changed to the past tense of 'feel', which is 『felt』, to fit the context of describing past events; ③ Adjective Error: 'feel cool' expresses a comfortable, pleasant coolness. When someone feels cool, they feel comfortable and pleased, usually not cold or uncomfortable. However, the intended meaning here is 'feeling cold and getting sick', so 〈cool〉 needs to be changed to 『cold』 to express the correct feeling; ④ Verb Choice Error: The fixed phrase for 'having a headache' is 'had a headache', not 'feel a headache'; therefore, 『had a』 is added to express the correct and complete meaning.

error_sentence: My friends let me went to hospital, doctor saied me fever.
correct_sentence: My friends took me to the hospital, and the doctor said I had a fever.
error: let me went to
correction: took me to the
error_type: Verb Choice Error
error_severity: 4
error_description: ① Verb Choice Error: The intended meaning is 'my friends took me to the hospital'. 〈let me went〉 does not conform to the causative verb structure; the correct expression would be 'let me go', but 'let me go' does not fit the context, as the prompt mentions 'my friends took me to the hospital'. Therefore, 『took me』 should be used to indicate the action of taking someone somewhere; ② Determiner Error: The noun 'hospital' 〈hospital〉 requires a definite article for modification; therefore, 『the』 needs to be added before it to comply with grammatical rules.

error_sentence: My friends let me went to hospital, doctor saied me fever.
correct_sentence: My friends took me to the hospital, and the doctor said I had a fever.
error: doctor saied me
correction: and the doctor said I had a
error_type: Sentence Structure Error
error_severity: 5
error_description: ① Conjunction Error: 'My friends let me went to hospital' and 'doctor saied me fever' are two clauses with independent predicate structures lacking a conjunction; therefore, 『and』 is needed to connect them and enhance sentence coherence; ② Determiner Error: 'doctor' is a singular countable noun and requires a determiner before it. Since it refers specifically to the doctor at the hospital at that time, the definite article 'the' should be added; ③ Spelling Error: According to English spelling rules, the simple past tense of 'say', 〈saied〉, is misspelled and should be corrected to 『said』; ④ Sentence Structure Error: According to English expression conventions, 〈saied me fever〉 is grammatically incorrect. A noun clause is needed after 'said' to introduce what the doctor said, which is 'I had a fever'; therefore, 『I had a fever』 replaces 〈me fever〉 to correctly express the situation of having a fever.

error_sentence: He gave me medicine and let me back home have a good free time.
correct_sentence: He gave me medicine and let me go back home and have a good rest.
correction: go
error_type: Verb Choice Error
error_severity: 3
error_description: Verb Choice Error: According to the fixed English usage, the expression for 'let someone do something' is 'let sb. do sth.'. Therefore, in 〈let me back home〉, a main verb indicating action is needed before 'back'. Using 『go back home』 expresses the meaning of 'go home'.

error_sentence: He gave me medicine and let me back home have a good free time.
correct_sentence: He gave me medicine and let me go back home and have a good rest.
correction: and
error_type: Conjunction Error
error_severity: 3
error_description: Conjunction Error: According to English grammar rules, the parallel verb phrases 〈go back home〉 and 〈have a good rest〉 need to be connected by the conjunction 『and』; therefore, 'and' is added between them.

error_sentence: He gave me medicine and let me back home have a good free time.
correct_sentence: He gave me medicine and let me go back home and have a good rest.
error: free time
correction: rest
error_type: Noun Error
error_severity: 3
error_description: Noun Error: The meaning of 〈have a good free time〉 does not fit the context. Based on the doctor's advice scenario, 『have a good rest』 should be used here to mean 'the doctor told me to rest'; therefore, 'free time' is changed to 'rest'.