Complex sentence: A common tactic of student protest is to go on strike (sometimes called a boycott of classes), whichoccurs when students enrolled at a teaching institution such as a school, college or university refuse to go to class.
Split into simpler sentences: A common tactic of student protest is to go on strike (sometimes called a boycott of classes). This occurs when students enrolled at a teaching institution such as a school, college or university refuse to go to class.