This is a paraphrasing task. In this task, you're given a sentence and your task is to generate another sentence which express same meaning as the input using different words.
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Question: when you see our mother , i want to know a day in advance , so i wo n't be there .

Answer: when you go to your mother , i want to know in advance .

Question: perhaps , when he wakes up , he can answer that question .

Answer: maybe when he wakes up , we get some answers .

Question: when she heard the news , um , she felt pity on me , and she called me .

Answer:
when she heard it , she felt sorry for her , so she called me .