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.

original sentence: Sid explained his theory to Mark but he couldn't convince him . paraphrase: Sid and Johnny explained their theory to Mark and Andrew but they couldn't convince them .
Number

original sentence: Bob paid for Charlie's college education . He is very grateful . paraphrase: Bob is paying for Charlie's college education . He is very grateful .
Tense

original sentence: Fred is the only man alive who still remembers my father as an infant . When Fred first saw my father , he was twelve years old . paraphrase: cosmo is the only man alive who still remembers my old man as an infant . when cosmo first saw my old man , he was twelve years old .

Synonym