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.

Q: original sentence: There is a pillar between me and the stage , and I can't see around it . paraphrase: There was a pillar between me and the stage , and I couldn't see around it .

A: Tense
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Q: original sentence: Billy cried because Toby wouldn't share his toy . paraphrase: Billy is crying because Toby won't share his toy .

A: Tense
****
Q: original sentence: I was trying to open the lock with the key , but someone had filled the keyhole with chewing gum , and I couldn't get it in . paraphrase: I am trying to open the lock with the key , but someone had filled the keyhole with chewing gum , and I can't get it in .

A:
Tense
****