1, If Jerry had answer, he would have understood
2, If Carol hadn't been studying, she would have answered the telephone
3, If he had studied hard enough, he wouldn't have failed in the exam
4, If I hadn't stuck in the traffic jam, I wouldn't have come late
5, If he hadn't gone out in the rain last night, he wouldn't have had the flu
6, If Jone had found the money, he would have returned it
7, If I had known you were there, I would called you
8, If it hadn't rained heavily, everybody would have gone out
9, If Jimmy hadn't lent me the money, I would have gone out with business
10, If you hadn't helped me, I wouldn't have succeeded this project