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: The drain is clogged with hair . It has to be removed . paraphrase: The drain was clogged with hair . It had to be removed .

Answer: Tense


Question: original sentence: Bob paid for Charlie's college education , but now Charlie acts as though it never happened . He is very hurt . paraphrase: Jane paid for Anne's college education , but now Anne acts as though it never happened . She is very hurt .

Answer: Gender


Question: original sentence: I used an old rag to clean the knife , and then I put it in the trash . paraphrase: I am using an old rag to clean the knife , and then I am putting it in the trash .

Answer:
Tense