People who don't know Harry tend to underestimate him. They cast a skeptical eye on his typical outfit: ragged jeans and shirts
that bear evidence of his most recent meal. And his most frequently uttered expression, "Hmmm, I just don't know," can make him sound less than bright. So, some enter a negotiating session with Harry relaxed and confident that their side will prevail, and that Harry will gain no concessions for his group. That assumption is one that Harry cultivates and it is a big, big mistake. What does the passage suggest about Harry? He is more clever than he seems. He is not as clever as he seems. He is not a skilled negotiator. He is aggressive in business.
Mechanical teacher was just a machine or computer which can teach but according to the level set without any kind of emotions whereas human teacher can make learning more easier according to the level of students who can understand their emotions as well.
