First vs. Second Condit/][onal:
The first conditional describes things that I think are likely to happen in the future, whereas the second conditional talks about things that I don't think will really happen. It's subjective; it depends on my point of view.
For example (first conditional): If she studies harder, she'll pass the exam (I think it's possible she will study harder and so she'll pass)
But (second conditional): If she studied harder, she would pass the exam (I think that she won't study harder, or it's very unlikely, and so she won't pass). Meer hierover als we de 2nd en 3rd conditional gaan bespreken.,