1. She is unhappy because he doesn't love her.....
She would be happy if he loved her
2. She was so happy yesterday because he told her he loved her.....
She wouldn't have been happy if he hadn't told her he loved her (She would have been unhappy if he hadn'n told her he loved her - т.к. два отрицания в английском не употребляют)
3. Glen stayed at home because the weather was bad.....
Glen wouldn't stayed at home if the weather was good
4. Molly doesn't trust him because she doesn't know him well....
Molly would trust him if she didn't know his well
5. He didn't argue because he didn't know the subject well.....
He would have argued if he had known the subject well
6. I didn't drink the coffee because it wasn't tasty......
I would have drunk the coffee if it had been tasty
7. The child learned the poem quickly because it was easy.....
The child wouldn't have learnt the poem quickly if it hadn't been easy (if it had been difficult)
8. I read a lot because I want to know a lot.....
I wouldn't read a lot if I didn't want to know a lot
9. I took the cat home because it looked unhappy......
I wouldn't have taken the cat at home if hadn'n looked unhappy (if it had looked happy)
10. I don't watch TV because I don't have much time......
I would watch TV if I haf much time