As a PhD student, you have some teaching duties. These most often consist of leading a bachelor’s course exercise class, correcting students’ homework and grading parts of exams. Dutch universities most often offer their bachelor’s courses in Dutch and therefore typically require more Dutch than foreign students. However, it may occur that several exercise classes of the same course are given in parallel, with one of them being given by a non-Dutch teaching assistant. PhD students also occasionally assist with master’s courses and supervise students of their own.
The limit for how much of your time you can devote to teaching duties is set at 10% in the collective labour agreement (article 12.2). This is just a maximum, however, meaning that you agree on the exact amount with your promotors and supervisors. Oftentimes, this will be recorded in your contract or your opleidings- en begeleidingsplan (education and supervising plan).
It is customary and advisable not to teach during the final year of the PhD programme. Additionally, you will most likely be unable to fulfill any teaching assistance during time you spend at CERN. This can cause your classes to stack up in the two years you are available, so discuss with your promotors and supervisors what the best course of action would be for your specific situation.