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?
