1.c  2.a  3.c  4.b   5.a   6.c  7.b  8.d   9.c    10.a 

11.b   12.d   13.c   14.b   15.a   16.d   17.a   18.b   19.c    20.a

VI. 
1. I didn't know it was your birthday, so I didn't send you a card.
=> If I had knew it was your birthday, I would have sent  you a card.
2. My brother didn't leave the car keys, so I couldn't pick him up at the station.
=>If my brother had left the car keys, I could have picked him up at the station.
3. You drink too much coffee, that's why you can't sleep.
=>If you didn't drink too much coffee, you could sleep.
4. I didn't have an umbrella with me so I got wet.
=>I wouldn't have got wet if I had had an umbrella with me
5. He didn't hury, so he missed the train.

=> if he had hurried, he wouldn't have missed the train.
6. Without Jack's help, I wouldn't have been able to move this table.
=> If there had not been Jack's help, I wouldn't have been able to move this table.
7. Make me some coffee, and I'll give you some sweets.
=> If you make me some coffee, and I'll give you some sweets.
8. I didn't have the money, so I didn't buy a new suit.

=> If I had had the money, I would have bought a new suit.

9. Stop talking or you won't understand thelesson.
=> If you stop talking, you will understand the lesson.
10. I'm not very dever, so I won't be a doctor.
=> If I were clever, I would be a doctor.

#TIB