Use this domain for words that mark the beneficiary of the Patient of an activity. The Patient is often expressed as the object of a sentence. In the sentence
"John built a house for his parents," the house is the Patient. It is the house that benefits the parents, not the building of the house.

Use this domain for words that mark the recipient of the Patient of an activity. The Patient is usually expressed as the object of a sentence.

Use this domain for words that mark a second Patient that accompanies the primary Patient of an activity. In this type of sentence there are actually two Patients, but one of them has more prominence than the other. The primary patient is usually expressed as the object of the sentence. The second Patient may be marked by an oblique case or preposition/postposition. For instance it may be conceived as accompanying the first Patient.