I-
1.can->could
2.know->knew
3.live->living
4.the->bỏ the
5.was->were
6.has risen->have been risen
7.will give->would give
8.taught->teaching
9.interest->interested
10.has retired->retired
II-
1.If they didn't behave themselves, their parents wouldn't be unhappy.
2.If she had said sorry, he wouldn't have been angry.
3.If I were a rich bussinessment, I could afford to buy the expensive car.
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