Помогите даю 15 баллов

1) If I pass my exam, I will be very happy.
2) If it stops raining, I will go for a walk with my family. 
3) If I had a headache, I would take a pill and take some rest.
4) If my friends had a problem, I would help them to solve it.
5) If I play well, I will win the competition.