1-If you become Prime Minister, I'll be happy. If he became Prime Minister, he'd increase taxation.
2-If it rains tomorrow, we will stay at home. If it rained tomorrow, the picnic would have to be put off.
3-If she learns to speak Spanish, I'll help her. If she learnt to speak Spanish, she'd get a good mark.
4-If wars stop, people will live in peace. If wars stopped, there would be less violent crime.
5-If he succeeds in life, he'll share with his success. If he succeeded in life, he'd help poor people.
6-If they support the child, he'll succeed in life. If they supported the child, he'd not get into trouble.
7-If I buy a cottage in the wood, I'll live there. If I bought a cottage in the wood, I'd spend summer holidays there.
8-If Annie married Stephen, Stephen would be the happiest man in the world.
9-If Nicholas studies harder, he'll pass the exam. If Nicholas studied harder, he probably would've passed the exam.
10-If Simon goes to University, he'll study well. If Simon went to University, he would've received a good education.