Sentence:  Particularly hard for the therapist to grasp are those instances in which the patient is <WSD>manifesting</WSD> an introject traceable to something in the therapist , some aspect of the therapist of which the latter is himself only poorly aware , and the recognition of which , as a part of himself , he finds distinctly unwelcome . 
Meaning of the word marked with <WSD> tags:  provide evidence for; stand as proof of; show by one's behavior, attitude, or external attributes