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: John ordered Bill to leave , so an hour later he left . paraphrase: Mary ordered Anne to leave , so an hour later she left .

Answer: Gender


Question: original sentence: Tom gave Ralph a lift to school so he wouldn't have to drive alone . paraphrase: Ralph was given a lift to school by Tom so he wouldn't have to drive alone .

Answer: Voice


Question: original sentence: The drain is clogged with hair . It has to be cleaned . paraphrase: The drain was clogged with hair . It had to be cleaned .

Answer:
Tense