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: We went to the lake , because a shark had been seen at the ocean beach , so it was a dangerous place to swim . paraphrase: We went to the lakes , because sharks had been seen at the ocean beaches , so they were dangerous places to swim .

SOLUTION: Number

PROBLEM: original sentence: Mary took out her flute and played one of her favorite pieces . She has had it since she was a child . paraphrase: Mary is taking out her flute and playing one of her favorite pieces . She has had it since she was a child .

SOLUTION: Tense

PROBLEM: original sentence: Bob paid for Charlie's college education . He is very grateful . paraphrase: Bob and Steve paid for Charlie and William's college education . They are very grateful .

SOLUTION:
Number