按要求完成句子用现在完成时改写下列句子，使A,B两句意思基本一致。每空限填一词。 1. A. We came to our school in 1980. B. We ________ ________ ________ our school since 1980. 2.A. The old woman died four years ago. B. The old woman ________ ________ ________ for four years. 3. A. The meeting began two hours ago. B. The meeting ________ ________ ________ for two hours. 4. A. I borrowed two books last week. B. I ________ the two books for a week. 5. A. When did the bus arrive here? B. How long ________ the bus ________ here?