1.If i hadn't be busy,i could have watched TV last night
2.If i had seen the signal,i would have stopped
4.If we hadn't stayed up late last night,we wouldn't be so tired.
3.If we had had a map ,we wouldn't have got lost.
5.If he had able...questions,he would not have failed the exam
6 If i hadn't be busy,i could have phoned you.
7.If i had had an umbrella,i would not have got wet in the rain
8.If Peter hadn't be very  nervous,he would not have failed the driving test
9.If i had had  money on me.i could have taken a taxi
10.If she had had a visa,she could have come to that country