How can I define that teacher can have max 3 consecutive periods(but he can have 2 doubles)

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First you would need to define that each teacher can have max 4 consecutive lessons:
Our teachers cannot teach more than 6 lessons consecutively

Then you need to say that each teacher can have max 3 consecutive single lessons:

Then you need to specify that teacher can have max 3 consecutive lessons where there are both single and doubles mixed:


Notes:
in both cardrelationships you might want to select relevant subjects, so that for example teachers preparation time and lunch are not counted into the consecutive periods count.