Studying:
(if-clause at the beginning)
Type I - If I study, I will pass the exam.
Type II - If I studied, I would pass the exam.
Type III - If I had studied, I would have passed the exam.
(if-clause at the end)
Type I - I will pass the exam if I study.
Type II - I would pass the exam if I studied.
Type III - I would have passed the exam if I had studied.