1) If she weren't so absent-minded, she would be a much better student. But she always forgets everything! (Действие происходит в настоящем времени, но не является реальным).
2) If you help me to translate this article, I will use it in my next report. (Действие происходит в настоящем, вполне реально).
3) If I were you I would consult immediatly my scientific adviser! (Наст. время, но не реально).
4) If you speak speak English every day you will improve your language skills. (Наст. время, реально).
5) If it rains tomorrow, we will cancel the outdoor experiment. (Настоящее, реальное).