Writing prompt: Using the information provided in Chinese and referring to the picture, write a short essay.
Mr. Cool's Clothes Store is having a big sale with great discounts. Sweaters in various colors are only 30 yuan, shorts are only 20 yuan, and shirts are only 25 yuan. Large bags sell for 35 yuan, and small bags for 20 yuan. There are also many beautiful shoes and skirts available. Welcome to shop.

Student essay:
The store is having a big discount, very favorable. Bags of various colors are only available for sale 30 yuan, shorts for 20 yuan, and shirts for 25 yuan. Big bags are solf for 20 yuan. There are sold for 20 yuan. There are also many beautiful shoes and skirts, welcome to choose.

Corrected essay:
The store is having a big discount, very favorable. Sweaters of various colors are available only for 30 yuan, shorts for 20 yuan, and shirts for 25 yuan. Big bags are sold for 35 yuan. Small bags are sold for 20 yuan. There are also many beautiful shoes and skirts. Welcome to choose.

Error analysis:
error_sentence: Bags of various colors are only available for sale 30 yuan, shorts for 20 yuan, and shirts for 25 yuan.
correct_sentence: Sweaters of various colors are available only for 30 yuan, shorts for 20 yuan, and shirts for 25 yuan.
error: Bags
correction: Sweaters
error_type: Noun Error
error_severity: 3
error_description: Noun Error: According to the prompt and sentence meaning, it refers to 'sweaters of various colors are only 30 yuan', so there is a noun error here. 〈Bags〉 needs to be changed to 『Sweaters』 to refer to sweaters, matching the prompt and sentence meaning.
error_sentence: Bags of various colors are only available for sale 30 yuan, shorts for 20 yuan, and shirts for 25 yuan.
correct_sentence: Sweaters of various colors are available only for 30 yuan, shorts for 20 yuan, and shirts for 25 yuan.
error: only available for sale
correction: available only for
error_type: Word Redundancy Error
error_severity: 4
error_description: ① Word Order Error: According to English grammar rules, the adverb 〈only〉 should be placed before the price number to mean 'only for...' to clarify the scope, so 〈only available〉 needs to be changed to 『available only』 to conform to English grammar rules and sentence meaning; ② Word Redundancy Error: According to English fixed phrases, the prepositional phrase 'for sale' means 'available for purchase', while 'for + specific price' means 'priced at xxx', so the redundant 〈sale〉 needs to be deleted to match the prompt and sentence meaning.
error_sentence: Big bags are solf for 20 yuan.
correct_sentence: Big bags are sold for 35 yuan.
error: solf for 20
correction: sold for 35
error_type: Number Error
error_severity: 3
error_description: ① Spelling Error: According to the sentence meaning, the past participle 'sold' of the verb 'sell' is needed here to indicate the passive voice, so the misspelled 〈solf〉 needs to be changed to 『sold』 to conform to English spelling norms; ② Number Error: According to the prompt requirements, the actual price of big bags is 35 yuan, not 20 yuan, so the number 〈20〉 needs to be changed to 『35』 to match the prompt.
error_sentence: There are sold for 20 yuan.
correct_sentence: Small bags are sold for 20 yuan.
error: There
correction: Small bags
error_type: Noun Error
error_severity: 3
error_description: Noun Error: According to the prompt, this refers to 'small bags sell for 20 yuan'. 〈There〉 as the subject of an existential sentence cannot convey specific product information, making the sentence subject unclear; thus, there is a noun error. The subject 〈There〉 needs to be replaced with 『Small bags』 to match the original prompt.
error_sentence: There are also many beautiful shoes and skirts, welcome to choose.
correct_sentence: There are also many beautiful shoes and skirts. Welcome to choose.
error: , welcome
correction: . Welcome
error_type: Punctuation Error
error_severity: 2
error_description: Punctuation Error: According to English writing conventions, the original sentences 〈There are also many beautiful shoes and skirts〉 and 〈welcome to choose〉 contain independent subject-verb structures and can stand alone as sentences, so there is a punctuation error here. 〈, welcome...〉 needs to be changed to 〈. Welcome...〉 to form two independent sentences.