Trying to help the student effectively butunobtrusively and naturally, the teacher is led to ask the same questions and to indicate the same stepsagain and again. Thus, in countless problems, we have to ask the question: What is the unknown? We mayvary the words, and ask the same thing in many different ways: What is required? What do you want tofind? What are you supposed to seek? The aim of these questions is to focus the student’s attention uponthe unknown. Sometimes, we obtain the same effect more naturally with a suggestion: Look at theunknown! Question and suggestion aim at the same effect; they tend to provoke the same mental operation