PART A.
1. If it rain, we will staying at home 
2. If you don't know the way, i will pick you up 
3. My mum will bake a cake if you come to see us.
4. They shall comes to his party if he invites them 
5. I will visits my grandparents if I have a long holiday
PART B.
1. If you studied harder, you could get better marks in your tests.2. If I were a rich, I would travel around the world.
3. She came to the market with us if she hadn’t to work.
4. We would sent you a message if we geted to the city.
5. I should call you back if I arrived at home.