You will be given two sentences. One of them is created by paraphrasing the original one, with changes on an aspect, or using synonyms. Your task is to decide what is the difference between two sentences. Types of change are explained below:
 Tense: The verbs in the sentence are changed in tense.
Number: Plural nouns, verbs and pronouns are changed into single ones or the other way around.
Voice: If the verbs are in active voice, they're changed to passive or the other way around.
Adverb: The paraphrase has one adverb or more than the original sentence.
Gender: The paraphrase differs from the original sentence in the gender of the names and pronouns.
Synonym: Some words or phrases of the original sentence are replaced with synonym words or phrases. Changes in the names of people are also considered a synonym change. Classify your answers into Tense, Number, Voice, Adverb, Gender, and Synonym.
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Question: original sentence: Adam can't leave work here until Bob arrives to replace him . If Bob had left home for work on time , he would be gone by this time . paraphrase: Adam couldn't leave work here until Bob arrived to replace him . If Bob had left home for work on time , he would have been gone by this time .

Answer: Tense


Question: original sentence: Fred and Alice had very warm down coats , but they were not prepared for the cold in Alaska . paraphrase: Fred and Alice certainly had very warm down coats , but they were not really prepared for the cold in Alaska .

Answer: Adverb


Question: original sentence: Dan took the rear seat while Bill claimed the front because his "Dibs!" was quicker . paraphrase: Dan is taking the rear seat while Bill is claiming the front because his "Dibs!" is quicker .

Answer:
Tense