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 here by this time . paraphrase: lance can't leave work here until rob arrives to replace him . if rob had left home for work on time , he would be here by this time .

Answer: Synonym


Question: original sentence: The firemen arrived after the police because they were coming from so far away . paraphrase: The fireman arrived after the policeman because he was coming from so far away .

Answer: Number


Question: original sentence: The police arrested all of the gang members . They were trying to stop the drug trade in the neighborhood . paraphrase: All of the gang members were arrested by the police . They were trying to stop the drug trade in the neighborhood .

Answer:
Voice