system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
The position or manner of use of an instrument is described by:
assistant
The correct answer is  Dr  Black  prescribed  four  classes,  similar  to  a  biological classification: 
Order - Purpose of instrument 
Suborder - Position or manner of use 
Class - Form of working end 
Subclass - Shape of the shank.