Four patidesaniya are (monastic) violations which must be verbally acknowledged: 1. Accepting and eating food from an unrelated bhikkuni. 2. Accepting and eating food after a bhikkuni has instructed the donors on who to give what food, and none of the bhikkus rebuke the bhikkuni. 3. Accepting and eating food from a family that the sangha designates as "in training", that is, preparing to becoming arahants, unless if the monk is sick. 4. Accepting and eating food from a family living in a dangerous location, unless if the monk is sick. (from the Vinaya Pitaka)