a) inserting the end effector into the mouth of a patient and translating the end effector to {HEAD ~ the esophagus} or the stomach of {TAIL ~ the patient} 
of
a ) inserting the end effector into the mouth of a patient and translating the end effector to { HEAD ~ the esophagus } or the stomach of { TAIL ~ the patient }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL