If I (have) time, I (pick) you up, but I am busy now.
If I had time, I would pick you up.
If you (not shout) so loudly, he (not be) so angry that evening.
If you had not shouted so loudly, he would not have been so angry that evening.
Your teacher isn't happy. If I (be) you, I (apologise) for such a behaviour.
If I were you, I would apologise for such a behaviour.