TASK DEFINITION: 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.
PROBLEM: original sentence: Sam took French classes from Adam , because he was known to speak it fluently . paraphrase: Sam took French classes from Adam , because he was known to speak it fluently .

SOLUTION: Voice

PROBLEM: 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 .

SOLUTION: Gender

PROBLEM: original sentence: The painting in Mark's living room shows an oak tree . it is to the right of the bookcase . paraphrase: The paintings in Mark's living room show oak trees . They are to the right of a bookcase .

SOLUTION:
Number